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: if one length of a square is tripled , and the original parameter is 4 y . what is the new length of one of the sides ? 
Options: ['a ) 12 y / 3', 'b ) 2 y / 2', 'c ) 6 y / 3', 'd ) 12 y / 4', 'e ) 4 y / 3']
Example Output: d

Example Input: Problem: a rectangular plot measuring 10 meters by 50 meters is to be enclosed by wire fencing . if the poles of the fence are kept 5 meters apart . how many poles will be needed ? 
Options: a ) 46 m , b ) 66 m , c ) 26 m , d ) 24 m , e ) 25 m
Example Output: d

Example Input: Problem: b takes 12 more days than a to finish a task . b and a start this task and a leaves the task 12 days before the task is finished . b completes 60 % of the overall task . how long would b have taken to finish the task if he had worked independently ? 
Options: a ) 48 days , b ) 36 days , c ) 28 days , d ) 32 days , e ) 22 days
Example Output:
b