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: two trains 140 m and 160 m long run at the speed of 60 km / hr and 40 km / hr respectively in opposite directions on parallel tracks . the time ( in seconds ) which they take to cross each other , is :
Options: a ) 9 , b ) 9.6 , c ) 10 , d ) 10.8 , e ) 7

Ex Output:
d

Ex Input:
Problem: walking with 5 / 4 of my usual speed , i miss the bus by 5 minutes . what is my usual time ?
Options: a ) 18 , b ) 19 , c ) 20 , d ) 22 , e ) 24

Ex Output:
c

Ex Input:
Problem: a jeep takes 9 hours to cover a distance of 480 km . how much should the speed in kmph be maintained to cover the same direction in 3 / 2 th of the previous time ?
Options: a ) 48 kmph , b ) 52 kmph , c ) 35 kmph , d ) 63 kmph , e ) 65 kmph

Ex Output:
c