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: a and b go around a circular track of length 400 m on a cycle at speeds of 36 kmph and 36 kmph . after how much time will they meet for the first time at the starting point ? 
Options: a ) 40 sec , b ) 198 sec , c ) 178 sec , d ) 665 sec , e ) 276 sec

Ex Output:
a


Ex Input:
Problem: along a yard 414 metres long , 24 trees are palnted at equal distances , one tree being at each end of the yard . what is the distance between two consecutive trees 
Options: a ) 18 , b ) 19 , c ) 10 , d ) 11 , e ) 12

Ex Output:
a


Ex Input:
Problem: a and b can do a piece of work in 30 days , while b and c can do the same work in 24 days and c and a in 20 days . they all work together for 10 days when b and c leave . how many days more will a take to finish the work ? 
Options: a ) 18 days , b ) 24 days , c ) 30 days , d ) 36 days , e ) 35 days

Ex Output:

a