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: the sum of 4 consecutive even numbers is 140 . what would be the smallest number ? 
Options: a ) 32 , b ) 88 , c ) 70 , d ) 123 , e ) 12

Ex Output:
a


Ex Input:
Problem: how long does a train 90 m long traveling at 60 kmph takes to cross a bridge of 170 m in length ? 
Options: a ) sec , b ) sec , c ) sec , d ) sec , e ) sec

Ex Output:
d


Ex Input:
Problem: a train 220 m long is running with a speed of 90 km / hr . in what time will it pass a bus that is running with a speed of 60 km / hr in the direction opposite to that in which the train is going ? 
Options: a ) 4.37 , b ) 5.28 , c ) 6.75 , d ) 8 , e ) 3.1

Ex Output:

b