Which of the following is an advantage of electric traction over other methods of traction?

A. Faster acceleration

B. No pollution problems

C. Better braking action

D. All of the above

Answer: D. All of the above

Explanation: 

Advantages of electric traction systems:

• It is cleanest of all other types of systems of traction; Due to this only it is ideally suitable for the underground and tube railways
• No need of storage of coal and water that in turn reduces the maintenance cost as well as the saving of high-grade coal
• Electric energy drawn from the supply distribution system is sufficient to maintain the common necessities of locomotives such as fans, lights; therefore, there is no need of providing extra generators
• The maintenance and running costs are comparatively low
• The speed control of the electric motor is easy
• Regenerative braking is possible so that the energy can be fed back to the supply system during the braking period
• In electric traction system, in addition to the mechanical braking, electric braking can also be used that reduces the wear on the brake shoes, wheels, etc.
• Electrically operated vehicles can withstand for overloads, as the system is capable of drawing more energy from the system
• High acceleration and braking retardation