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 the wheel is 12 cm then the number of revolutions to cover a distance of 1240 cm is ?
Options: a ) 11 , b ) 14 , c ) 16 , d ) 12 , e ) 19

Ex Output:
c

Ex Input:
Problem: a can do a work in 15 days and b in 20 days . if they work on it together for 5 days , then the fraction of the work that is left is :
Options: a ) 1 / 3 , b ) 7 / 12 , c ) 5 / 12 , d ) 2 / 3 , e ) 1 / 2

Ex Output:
c

Ex Input:
Problem: two passenger trains start at the same hour in the day from two different stations and move towards each other at the rate of 16 kmph and 22 kmph respectively . when they meet , it is found that one train has traveled 60 km more than the other one . the distance between the two stations is ?
Options: a ) 565 , b ) 444 , c ) 676 , d ) 456 , e ) 663

Ex Output:
d