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 can do a piece of work 60 days . b can do work in 20 days . in how many days they will complete the work together ?
Options: a ) 12 days , b ) 16 days , c ) 15 days , d ) 17 days , e ) 18 days
Example Output: c

Example Input: Problem: a train speeds past a pole in 15 sec and a platform 100 m long in 25 sec , its length is ?
Options: a ) 158 m , b ) 150 m , c ) 110 m , d ) 130 m , e ) 157 m
Example Output: b

Example Input: Problem: the length of a room is 5.5 m and width is 3.75 m . find the cost of paying the floor by slabs at the rate of rs . 1200 per sq . metre .
Options: a ) rs . 15,000 , b ) rs . 24,750 , c ) rs . 15,600 , d ) rs . 16,500 , e ) none
Example Output:
b