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: to fill a tank , 20 buckets of water is required . how many buckets of water will be required to fill the same tank if the capacity of the bucket is reduced to one - fifth of its present ? 
Options: a ) 100 , b ) 200 , c ) 300 , d ) 400 , e ) 500

Ex Output:
a


Ex Input:
Problem: a train 200 m long is running with a speed of 68 kmph . in what time will it pass a man who is running at 8 kmph in the same direction in which the train is going ? 
Options: a ) 6 sec . , b ) 7 sec . , c ) 9 sec . , d ) 12 sec . , e ) none

Ex Output:
d


Ex Input:
Problem: a train covers a distance of 6 km in 10 min . if it takes 12 sec to pass a telegraph post , then the length of the train is ? 
Options: a ) 120 m , b ) 180 m , c ) 240 m , d ) 220 m , e ) 280 m

Ex Output:

a