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: three pipes of same capacity can fill a tank in 8 hours . if there are only two pipes of same capacity , the tank can be filled in . 
Options: a ) 11 hours , b ) 12 hours , c ) 15 hours , d ) 16 hours , e ) 17 hours

Ex Output:
b


Ex Input:
Problem: in a 500 m race , the ratio of the speeds of two contestants a and b is 3 : 4 . a has a start of 155 m . then , a wins by : 
Options: a ) 60 m , b ) 20 m , c ) 40 m , d ) 20 m , e ) 23 m

Ex Output:
c


Ex Input:
Problem: a wooden box of dimensions 8 m x 3 m x 6 m is to carry rectangularboxes of dimensions 8 cm x 3 cm x 2 cm . the maximum number ofboxes that can be carried in the wooden box , is 
Options: a ) 9800000 , b ) 1000000 , c ) 7500000 , d ) 3000000 , e ) none of these

Ex Output:

d