MMV S 3

MECHANIC MOTOR VEHICLE
(THEORY)
SEMESTER – III 
JULY 2018
The clutch cover is bolted to ….
a. Fly wheel
b. Car frame
c. Engine block                                                                                                                                          d. Clutch disc                                                                                                                                              Answer: a. Fly wheel
itiquestion.blogspot.com

The following provides a smooth means of
disengagement and engagement between the
engine and the remainder of transmission system-
a. Clutch
b. Gearbox
c. Propeller shaft
d. Differential
Answer: a. Clutch

The torque which a clutch can transmit, depends upon the-
a. Coefficient of friction
b. Spring force
c. Contact surfaces
d. All of these
Answer: d. All of these

Mechanical transmission can be of following class(es) ….
a. Clutch, gearbox and live axle transmission
b. Clutch, gearbox and dead axle transmission
c. Clutch, gearbox and axle less transmission .
d. All of the above
Answer: d. All of the above

Which type of gear box is used in automobiles?
a. Sliding mesh gear box
b. Differential gear box
c. Synchromesh g
d. All of these
Answer: d. All of these
itiquestion.blogspot.com

Four-wheel drive vehicles have differential at …..
a. Front wheels
b. Rear wheels
c. Both the front and rear wheels
d. Any of the front or rear wheels
Answer: c. Both the front and rear wheels


The differential unit consists …….
a. One bevel pinion
b. Two bevel pinion
c. Three bevel pinion
d. Four bevel pinion
Answer: b. Two bevel pinion
Which of the following is a higher pair?
a. Turning pair 
b. Screw pair
c. Belt and pulley
d. None of these
Answer: c. Belt and pulley

For a simple gear train, velocity ratio is the ratio of ……………
a. Speed of driving shaft and speed of driven shaft
b. Speed of driven shaft and speed of driving shaft
c. Speed of driven shaft and (speed of driving shaft + speed of idler gears)
d. Speed of driving shaft and (speed of driven shaft + speed of idler gears)
Answer: b. Speed of driven shaft and speed of driving shaft
itiquestion.blogspot.com

In a simple gear train, if the number of idle gears is odd, then the motion of driven gear will-
a. Be same as that of driving gear
b. Be opposite as that of driving gear
c. Depend upon the number of teeth on the driving gear
d. None of the mentioned
Answer: a. Be same as that of driving gear

To connect two parallel and coplanar shafts the following type of gearing is used-
a. Spur gear
b. Bevel gear
c. Spiral gear
d. None of these
Answer: a. Spur gear

In which of the following type of gear train the first gear and the last gear are co-axial.
a. Simple gear train
b. Compound gear train
c. Reverted gear train
d. None of these
Answer: c. Reverted gear train

Transfer case is located next to the gearbox in …..
a. Front wheel drive
b. Rear wheel drive
c. Four wheel drive
d. All of these
Answer: c. Four wheel drive
itiquestion.blogspot.com

Which of the following is not an example of recuperations' type heat exchanger?
a. Automobile radiators
b. Condensers
c. Chemical factories
d. Oil heaters for an aero
Answer: c. Chemical factories

In Disc clutch, the clutch disc acts as a ……
a. Driving member
b. Driven member
c. Neutral member
d. Any of these
Answer: b. Driven member

The following components forms valve operating mechanism except …..
a. Push rod .  .
b. Rocker arm
c. Valve seat
d. Fork
Answer: d. Fork

Machine member used to connect engine shaft to gear box is cal led-
a. Differential
b. Clutch
c. Flywheel
d. Propeller shaft
Answer: b. Clutch
itiquestion.blogspot.com

Which type of clutch does not require clutch pedal?
a. Single plate
b. .Multi plate
c. Centrifugal
d. Cone
Answer: c. Centrifugal

The valve is opened as the cam lobe on the cam raises the …..
a. Bearing
c. Valve lifter
b. Piston
d. Valve seat
Answer: c. Valve lifter

The size of the engine intake valve is ……………
a. Same as that of exhaust valve
b. Smaller than that of exhaust valve ,
c. Larger than that of exhaust valve
d. Does not depend upon the size of exhaust valve
Answer: b. Smaller than that of exhaust valve
itiquestion.blogspot.com

The purpose of valve clearance is to ………..
a. Allow the valve to expand
b. Allow the sliding of valve in the guide
c. Ensure that the valve closes fully
d. Ensure that the crankshaft is free to rotate
Answer: c. Ensure that the valve closes fully

A relief valve is fitted to the main oil gallery of an engine.
The purpose of this valve is to-
a. Limit the maximum oil pressure
b. Open when the oil is hot
c. Maintain the supply if the gallery becomes blocked
d. Stop the oil flow to the bearings
Answer: a. Limit the maximum oil pressure

Which vehicle is generally provided with four wheel drive?
a. Ambassador car
b. Standard wagon
c. Matador
d. Jeep
Answer: d. Jeep

Leaf springs absorb shocks by ………..
a. Bending
b. Twisting
c. Compression
d. Tension
Answer: a. Bending
itiquestion.blogspot.com

The following is (are) the independent suspension system(s) …..
a. Wishbone Arm system
b. Trailing Link system
c. Sliding Pillar system
d. All of these
Answer: d. All of these

The Ackermann steering iayout ……..
a. Makes for safer driving
b. Enables the driver to feel ahead position
c. Reduces load on the kingpins and stub axles
d. None of the above
Answer: a. Makes for safer driving

In disc brake, the disc is attached to the ………
a. Wheel
b. Axle
c. Suspension system
d. None of these
Answer: b. Axle
itiquestion.blogspot.com

The function of master cylinder in hydraulic brakes is to ……….
a. Builds up hydraulic pressure to operate the brakes
b. Maintains constant volume of fluid in the system
c. Serves as a pump to force air out of the hydraulic system
d. All of the above
Answer: d. All of the above

The following factor(s) contribute to the effectiveness of the brakes ………..
a. Area of brake linings
b. Radius of car wheel
c. Amount of pressure applied to shoe brakes
d. All of the above
Answer: d. All of the above
itiquestion.blogspot.com

The process of removing air from the brake system is known as …..
a. Bleeding
b. Self-energizing .
c. Servo action
d. Energization
Answer: a. Bleeding

When brakes are applied on a moving vehicle;
the kinetic energy is converted to ……..
a. Mechanical energy
b. Heat energy
c. Electrical energy
d. Potential energy
Answer: b. Heat energy

The force required to stop a vehicle is dependent on ……
a. The weight of vehicle
b. The deceleration rate
c. Both a and b
d. None of these
Answer: c. Both a and b

Coil springs absorb shocks by……….
a. Bending
b. Twisting
c. Compression
d. Tension
Answer: c. Compression

The following is a type of leaf springs ……….
a. Three Quarter elliptic
b. Semi elliptic
c. Quarter elliptic
d. All of these
Answer: d. All of these
itiquestion.blogspot.com

The material used for making torsion bar is ………
a. Steel
b. Cast iron
c. High carbon steel
d. All of these
Answer: a. Steel

Spring shackles are used to join ……….
a. Chassis frame and spring
c. Chassis frame and axle
b. Spring and Axle
d. All of these
Answer: a. Chassis frame and spring

Cam actuated double acting hydraulic shock absorber contains ……..
a. No piston
b. Single piston
c. Double pistons
d. Three pistons
Answer: c. Double pistons

The main reasons for crankshaft wear are ………….
a. Different loads at some points of rotation
b. Centrifugal forces due to crankshaft rotation
c. Misalignment in connecting rod
d. All of the mentioned
Answer: d. All of the mentioned
itiquestion.blogspot.com


The main causes of crankshaft vibration are ………
a. Variation in torque
b. Cyclic variation of gas and combustion products
c .Unbalanced weight of parts
d. All of the mentioned
Answer: . d. All of the mentioned

In the cam, the distance between the base circle and the nose is called ……..
a. Lift
b. Lobe
c. Flank
d. Pitch
Answer: a. Lift

The function of anti-lock brake system (ABS) is that is ………….
a. Reduces the stopping distance .
b. Minimizes the brake fade
c. Maintains directional control during braking by preventing the wheels from locking
d. Prevents nose dives during braking and thereby postpones locking of the wheels
Answer: c
itiquestion.blogspot.com

In a four wheel drive (4 WD), the numbers of gear boxes are ……………
a. 1
b. 2
c. 3
d. 4
Answer: b. 2

In the steering gear, a gear sector or toothed roller is meshed with a …….
a. Ball bearing
b. Roller bearing
c. Worm
d. Steering wheel
Answer: c. Worm
itiquestion.blogspot.com

The only service that a steering linkage normally requires is ……….
a. Tie-rod adjustment
b. Lubrication
c. Ball-joint replacement
d. None of the mentioned
Answer: a. Tie-rod adjustment

Too much toe-in will be noticed by ……….
a. Excessive tyre wear because of taking
b. Steering wander
c. Feathering of tyres
d. Light steering
Answer: a. Excessive tyre wear because of taking
itiquestion.blogspot.com

The most widely used-brakes are operated ………
a. Electrically
b. Hydraulically
c. By air pressure
d. By vaccum
Answer: b. Hydraulically

Of  the four tyres on a car, the one that wears most is ……
a. Right front tyre
b. Right rear tyre
c. Left front tyre
d. Left rear tyre
Answer: b. Right rear tyre

Weight can be attached to wheel rim to correct ……..
a. Wheel alignment
b. Wheel balance
c. Wheel run out
d. All of these
Answer: b. Wheel balance

Steering gear …….
a. Rack and pinion type
b. Worm and roller type
c. Recirculating ball type
d. Any of  these
Answer: d. Any of  these
itiquestion.blogspot.com

Wheel base of a vehicle is the ……
a. Distance between front and rear axles
c. Extreme length of the vehicle
b. Distance between the front tyres
d. Width of tyres

Answer: a. Distance between front and rear axles

MMV sem 3 jan 2015 theory questions
Which one is over all length of the vehicle from the given specification ?
A   4or6   B  746 watts  C   5 ton   D   1600m.m

Who is the first inventor of compression type ignition diesel engine ?
A  Nicholas otto  B  Rudolph diesel   C Benz    D Perkins

Pressure plate is mounted on the.....................
A  fly wheel    B  clutch cover     C  clutch disc    D  crank shaft

In the transmission system, which unit is disengages the drive and provides a smooth take up of the drive ?
A Clutch    B  Gear box    C  Propeller shaft   D  Final drive

The vehicle attains different speed by means of..............
A  gear box   B dutch   C differential   D  rear axJe & wheel

Which among the following bearing can take axial load in both the direction ?
A   Needle bearing   B   Ball bearing   C   Tapper roller bearing    D  Bush bearing

In the gear box which shaft is connected to the propeller shaft flange ?
A   Top gear shaft   B   Lay shaft    C   Main shaft   D   Reverse gear shaft


By using synchronizing device , the tw  involved mating gears have their speed...............
A increased   B reduced    C equalised      D unequalized


The vehicles having automatic transmission connect the engine to the gear box by means of a........
A. dog clutch    B. fluid coupling   C. dry friction clutch    D. wet friction clutch

When the four wheel drive is to be used ?
A   Moving on the pitch road                          B   Moving on the cement road
C   Moving on the sand and slushly ground    D   Moving on the high ways

In a Hotchkiss drive the rear end driving torque is taken up by.............
A  rear axle housing   B  rear leaf spring     C  shock absorber   D  engine mounting

Constant velocity universal joint is used at the............
A   front end of the propeller shaft
B    rear end of the propeller shaft
C    rear wheel end of the shaft in front wheel drive vehicles
D    differential end of the shaft in rear wheel drive vehicles

Which type of universal joint is mostly used in heavy commercial vehicles ?
A   Spider and yoke type  B    Ball and trunnion   C   Constant velocity type    D    Rubber mould type


Which one of the following arrangement is mostly used in heavy commercial goods vehicle?
A   Front engine - front wheel drive   B   Front engine - rear wheel drive
C   Rear engine -rear wheel drive       D   Rear engine - front wheel drive

Normally the transfer case unit is used for.................
A  front wheel drive  B  centre wheel drive  C  rear wheel drive  D  four wheel drive


What i$ the drive mechanism mostly provided the morden cars ?
A. Front engine - front wheel drive   B. Front engine - rear wheel drive
C. Rear engine - front wheel drive    D. Rear engine - rear wheel drive

The distance between adjacent mating gears is called...............
A  heel   B   pitch line   C   back lash     D   flank

Over drive gear ratio is...............
A    1 to 3    B    1 to 2     C   1 to 1     D    1 to 0.7

Transaxle is integral part of....................
A clutch      B gear    C differential   D engine

Which type of steering gearbox is mostly used in heavy commercial vehicles ?
A  Rack and pinion type         B  Worm and roller type
C  Worm and wheel type        D  Worm and re-circulating ball type

in brake wheels get locked before the vehicles stops. The wheels are said tobe..........
A slipping    B sliding   C skidding   D rubbing

In disc brake system, to which component the disc is attached ?
A Piston  B Caliper   C Wheel hub  D Steering krunckle

If the negative camber is excessive , what will happen in tyre wear ?
A  Tyre inner edge will wear faster    B  Tyre centre portion wiii wear faster
C  Tyre outer edge will wear faster    D  Tyre side walls will wear faster

In the power steerings, the oil pump drive gear is driven by...........
A  engine crank shaft   B  engine cam shaft   C  engine rocker shaft  D  FIP cam shaft


In disc brakes, pad-to-disc adjustment is provided by............
A caliper  B piston  C brake cam  D bleed screw

In the fail safe air brake system spring brake actuators are used for the.........
A  front brakes  B  rear brakes  C  LH side brakes  D  RH side brakes

The operation of removing trapped air from hydraulic braking system is known as..........
A tapping  B bleeding  C removing  D clearing

How the brakes are applied in fail safe air brake system during parking ?
A   By air pressure in brake actuator
B   By spring pressure in brake actuator
C   By vacuum in brake actuator
D   By mechanical hand brake

In master cylinder, the partial vacuum helps in the following manner...........
A   to draw brake fluid from main port
B   to draw brake fluid from compersating port
C   to draw brake fluid from both ports simultaneously
D   does not allow fluid into the cylinder

What is the expands of ABS ?
A  Air Brake System      B  Anti Booster System
C  Air Booster System    D  Antilock Brake System

In ABS brake system of vehicles, the wheel sensors are...............
A   filted infront wheels only B   filted in rear wheels only
C   filted in all wheels           D   not filted in any wheel

The leaf spring assembly used in which type of suspension system ?
A   Conventional suspension system  B   dependent suspension system
C   Air suspension system                  D   Rubber spring suspension system

The rubber bellows are used in which type of suspension system ?
A   Conventional suspension system  B   Indipendent suspension system
C   Air suspension system  D   Rubber spring suspension system

How a leaf spring assembly is connebted with the main axle ?
A ' U ' Clamp /' I 'bolt  B  Shackle unit  C  'C clamp  D  Spring pin

Which type of the shock absorber is used in mordern cars ?
A  Soiid type   B  Rigid type   C  Telescopic type  D  Hinge type

The function of the shackle In a leaf spring is to.......
A  allow pivoting of spring end   B  allow the spring length to change
C  control side way                      D  control rear torque

Helper spring is used in..................
A. cars  B. jeep   C. medium motor vehicle   D. heavy trucks

When a vehicle is parked in a garage on plain surface, the shock absorber is in............
A   parfialy compressed state  B   fully compressed state
C   fully expanded state          D   twisted state

Generally, clutch peda! free travel (play) is adjusted by..........
A  placing shims under the clutch cover   B  adjusting the clutch linkages
C  bend the pedal stop                              D  align the clutch hausing

Constant velocity joint have........
A  one cross  B  one flanger yoke   C  one tube yoke   D  two crosses, one flange yoke and one tube yoke

Transmission fluid is generally.....................
A blue colour   B green colour   C red colour   D clear

Toe -in is adjusted by altering the..................
A  angle of track arm                  B  length of track rod
C  distance between the king pin D  position of the drag link

If a tyre specification is 9" * 14 "PR. what is the meaning of 9" in the specification
A  diameter of tyre  B  width of tyre  C  ply rating D  diameter of rim

When the piston moves upward in the shock absorber, which valve is open in piston ?
A  Foot valve to reservoir  B  Rebound valve  C  Foot valve to cylinder  D  Bump valve

What type of tyre has a slow deflation when punctured ?
A Tube cross - ply  B Tube radial - ply   C Tubeless cross - ply  D Tubeless radial -ply

The tread will wear for under inflated tyres on........
A at the centre   B at the edges   C heel and toe   D feathery type

"Light motor vehicle" means gross vehicle weight does not exceed...........
A 12,000 kilograms  B 10,000 kilograms  C  8,000 kilograms  D  6,000 kilograms

The person steers and controls a running vehicle is called.........
A conductor    B driver  C passenger   D ticket checker

Which one is regulatory sign ?
A  Guarded railway crossing   B  Steep ascent  C  Restriction end   D  Resting place

What is not required to renewal of driving licence ?
A  Appropriate fee as specified in rule 32     B  3 recant photograph copies of the applicant's
C  Learners license                                       D  The medical certificate in 3[form1-A]


Jan18 MECHANIC MOTOR VEHICLE THEORY SENESTER III

A mechanism which enables to the rotary motion of one shaft to another shaft at the same axis is called —
a) Crank
b) Differential
c) Clutch
d) Fly wheel

The main advantage of a good clutch is —
a) Good power transmission
b) Rapid engagement
c) Rapid disengagement
d) Large size

The cushioning springs in clutch plate are used to reduce
a) Vibrations
b) Jerks
c) Vehicle speed
d) NC ne of these

The clutch disc is positioned between the flywheel and the
a) Engine
b) Crankshaft
c) Pressure plate
d) Differential

The diaphragm clutch is generally used in
a) Modem cars
b) Dual mass flywheel
c) Tractors
d) Automatic transmission

"Clutch slippage" when the clutch is engaged is particJlarly noticeable —
a) At low speed
b) At Idling
c) During acceleration
d) While starting the engine

Most ofthe vehicles having automatic transmission, connect the engine to the gearbox through
a) Multi-plate clutch
b) Dog clutch
c) Magnetic clutch
d) Fluid clutch (fluid coupling or torque converter)

The synchronizer hub is attached with main shaft through
a) Synchronizer key
b) Shifl fork
c) Synchronizer ring
d) Splines inside the hub
If the tractive effort is the highest -(ör a given velocity, then vehicle must be in —
a) Top gear
b) Third gear
c) Second gear
d) First gear

The component in the torque converter which allows multiplication of the torque is -
a) Pump
b) Stator
c) Turbine
d) Impeller

The main disadvantage of sliding mesh transmission is —
a) High noise level
b) Low mechanical efficiency
c) High skilled required by the driver
d) All of these

The purpose of synchromesh mechanism is to
a) Run the driving and driven gear shafts at different speed
b) Synchronize the speed of driving and driven gear shafts
c) Increase the torque
d) Decrease the torque

In simple planetary gear, the member which increases the torque is —
a) Ring — gear
b) Sun-gear
c) Planet carrier
d) None of these

In a torque converter, the maximum torque multiplication occurs at --
a) Stop
b) Low speed
c) Medium speed
d) High speed

The functions of Electronically controlled automatic transmissions is to
a) Downshift automatically when going downhill to control speed
b) Up shift automatically when braking on a slippery surface
c) Prevent the up shift when taking a turn
d) All ofthe above

In Hydraulic fluid controlled automatic transmission, the shifting of gears is based on
a) Govemor and throttle pressure b) Only governor pressure
c) Only throttle pressure
d) None of these

The probable cause for gear jumps out of mesh is.
a) Weak spring or fork rod
b) Flywheel housing and gearbox out of alignment
c) Worn out teeth of sleeve or gears
d) Any of the above

Interlocking mechanism is provided in the shift mechanism of manual transmission is to-
a) Prevent shifting of two gears simultaneously
b) Prevent shifting of reverse gear
c) Facilitate the gear selection
d) All of the above

In a simple gear train if number of idle gear is even then the direction of motion of driven gear will be-
a) Same as driving gear
b) Opposite to the driving gear
c) Depending on number of teeth on the driving gear
d) Depending on number of teeth on the driven gear

The smaller gears inside the differential casing are-
a) Pinion gears
b) Sun gears
c) Ring gears
d) None of these

The type of rear axle used in trucks is-
a) Semi floating b) Fully floating
c) Three quarter floating
d) None of these

The limited slip differential (LSD) mechanism comes in action when-
a) Driving on bumpy roads
b) One tyre encounters a slippery section of road
c) When cornering at high speed
d) All of the above

In most of the modern cars which type of drive is employed on the wheels-
a) Front 2 — wheel drive
b) Rear 2 — wheel drive
c) 4 — wheel drive
d) All wheel drive

Most popular manual steering gear for cars is-
a) Worm and wheel type
b) Worm and nut type
c) Rack and Pinion type
d) Re — circulating ball type

One purpose of re-circulating ball type steering gear is to reduce-
a) Toe out during tum
b) Operating friction
c) Operating cost
d) None of these

The power steering pump is-
a) Belt driven by camshaft  
b) Chain driven by crank shaft
c) Chain driven by cam shaft
d) Belt driven by crank shaft

The purpose of caster is to-
a) Ensure steering stability
b) Reduce the rolling resistance which the tyres may encounter during a tum
c) Enables the vehicle to be towed easily
d) Cancel the tendency of toe-out

The elecm)nic power steering (EPS) system control unit controls the assist motor based on signals of-
a) Road resistance, steering turning speed and vehicle speed
b) Road resistance, steering turning direction and engine speed
c) Road resistance, steering turning direction and vehicle speed
d) Road resistance, steering turning speed and engine speed

The effect of excessive camber is-
a) High steering alignment torque   b) Hard steering
c) Too much traction d) Un even tyre wear

The function which allows the driver to raise or lower the steering wheel is-
a) Power steering system
b) Tilt steering system
c) Air bag system
d) Rack and pinion type steering system

Which of the following can be adjusted by modifring the tie — rod attachment length?
a) Camber
b) Caster
c) Toe-in or Toe-out
d) Steering gear ratio

The name of component that connects the rack to the steering knuckles is-
a) Tie rod
b) Sector arm
c) Pivot
d) Spline

The vehicle ride will be comfortable if-
a) Un-sprung weight is kept minimum
b) Un-sprung weight is kept maximum
c) Sprung weight is kept minimum
d) Vehicle weight is kept minimum

The spring commonly used in modern cars is-
a) Semi elliptical leaf spring
b) Coil spring
c) Quarter elliptical leaf spring
d) Elliptical leaf spring

The part which permits variation in the distance between the spring eyes of a leaf spring   as the spring flexes, is called-
a) U — bolt b) Shackle

c) Leaf d) Bush

In which type of suspension the compressed air is necessary-
a) Rigid axle suspension
b) Air suspension
c) Mc-Persion strut suspension
d) Double wishbone suspension

A damper is also known as-
a) Torsion bar
b) Spring
c) Stabilizer
d) Shock absorber

An under -- inflated tyre wear out more-
a) Near centre
b) Near edge
c) In cross section
d) In lateral direction

The part ofthe tyre which contacts the road surface is called-
a) Carcass
b) Bead
c) Tread
d) Ply

The term "ply rating" with reference to a tyre refers to the-
a) Actual number of plies
b) Recommended inflation pressure
c) Aspect ratio
d) Rated strength

The efficiency of mechanical brakes is usually-
a) 30-40%
b) 40-50%
c) 50-60 %
d) 60-70%

'Brake Fade' is-
a) Loss of pedal free play
b) Loss of hydraulic fluid
c) Loss of co-efficient of friction
d) Change of colour of the lining due to oil soaked by lining


The brake bleeding process removes from the hydraulic brake system.
a) Air
b) Vacuum
c) Excess fluid
d) Excess pressure

The role of Antilock Brake System (ABS) is that-
a) It reduces the vehicle's stopping distances
b) It minimizes brake fade
c) It maintains directional control during braking by preventing the wheels from locking
d) It prevents nose during braking and thereby postpones locking of the wheels

When the hydraulic brake pedal is pressed by the driver and feels 'spongy' it indicates that-
a) Brake shoe clearance is excessive
b) System contains air
c) System is in good condition
d) Brake fluid require change

Which of the following problem is caused due to wheel imbalance?
a) Steering wheel vibration
b) Poor acceleration
c) Reduced fuel efficiency
d) Road noise

The purpose oftyre rotation on automobile is to-
a) Avoid ply separation
b) Equalize wear
c) Get better ride
d) None of these

If driving incense for a privately driven vehicle is expired then you can get your license renewed for a maximum period of-
a) 3 years from the date of expiry b) 4 year from the date of expiry
c) 5 years from the date of expiry d) 6 years from the date of expiry

For a new petrol run private vehicle, the initial fitness certificate is valid for-
a) 20 years
b) 15 years
c) 10 years
d) 05 years

The violation of which road signs is a legal offence?
a) Mandatory sign
b) Cautionary signs
c) Informatory signs
d) Any of these

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