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 train 250 m long running at 72 kmph crosses a platform in 15 sec . what is the length of the platform ? 
Options: a ) 50 m , b ) 200 m , c ) 250 m , d ) 270 m , e ) 300 m

Ex Output:
a


Ex Input:
Problem: a horse chases a pony 8 hours after the pony runs . horse takes 12 hours to reach the pony . if the average speed of the horse is 320 kmph , what s the average speed of the pony ? 
Options: a ) 182 kmph , b ) 192 kmph , c ) 193 kmph , d ) 196 kmph , e ) 190 kmph

Ex Output:
b


Ex Input:
Problem: a can fill tank in 9 minutes , b can empty the tank in 18 minutes . . in what time the tank be filled , if both pipes work simultaneously ? 
Options: a ) 14 minutes , b ) 15 minutes , c ) 16 minutes , d ) 17 minutes , e ) 18 minutes

Ex Output:

e