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'.

Example Input: Problem: a 300 m long train crosses a platform in 45 sec while it crosses a signal pole in 18 sec . what is the length of the platform ? 
Options: a ) 287 , b ) 350 , c ) 828 , d ) 450 , e ) 122
Example Output: d

Example Input: Problem: in a kilometer race , a beats b by 40 meters or 10 seconds . what time does a take to complete the race ? 
Options: a ) 290 sec , b ) 190 sec , c ) 199 sec , d ) 192 sec , e ) 240 sec
Example Output: e

Example Input: Problem: a person can row at 10 kmph in still water . if the velocity of the current is 2 kmph and it takes him 10 hour to row to a place and come back , how far is the place ? 
Options: a ) 24 km , b ) 30 km , c ) 48 km , d ) 12 km , e ) 48 km
Example Output:
e