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 kmph and 40 kmph in opposite directions in parallel tracks . the time which they take to cross each other is ? 
Options: a ) 5.6 sec , b ) 8.9 sec , c ) 10.8 sec , d ) 12.6 sec , e ) 15 sec

Ex Output:
c


Ex Input:
Problem: if the wheel is 14 cm then the number of revolutions to cover a distance of 968 cm is ? 
Options: a ) a ) 15 , b ) b ) 10 , c ) c ) 14 , d ) d ) 12 , e ) e ) 11

Ex Output:
e


Ex Input:
Problem: a can do a piece of work in 4 hours ; b and c together can do it in 3 hours , while a and c together can do it in 3 hours . how long will b alone take to do it ? 
Options: a ) 12 , b ) 9 , c ) 8 , d ) 6 , e ) 4

Ex Output:

e