In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: if a train , travelling at a speed of 180 kmph , crosses a pole in 5 sec , then the length of train is ? 
Options: a ) 250 m , b ) 112 m , c ) 117 m , d ) 125 m , e ) 123 m

Ex Output:
a


Ex Input:
Problem: the cyclist going at a constant rate of 20 miles per hour is passed by a motor - cyclist traveling in the same direction along the same path at 60 miles per hour . the motor - cyclist stops to wait for the cyclist 10 minutes after passing her , while the cyclist continues to travel at constant rate , how many minutes must the motor - cyclist wait until the cyclist catches up ? 
Options: a ) 10 , b ) 20 , c ) 25 , d ) 30 , e ) 40

Ex Output:
b


Ex Input:
Problem: area of four walls of a room is 99 m 2 . the length and breadth of the room are 7.5 m and 3.5 m respectively . the height of the room is : 
Options: ['a ) 2.5 m', 'b ) 3.5 m', 'c ) 1.5 m', 'd ) 4.5 m', 'e ) 5.5 m']

Ex Output:

d