In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Example Input: Problem: sum of two numbers is 63 . their difference is 1 / 8 of their sum . their l . c . m is 
Options: a ) 231 , b ) 153 , c ) 351 , d ) 345 , e ) 355
Example Output: c

Example Input: Problem: x + ( 1 / x ) = 1.5 find x ^ 2 + ( 1 / x ^ 2 ) 
Options: a ) 2.25 , b ) 3.25 , c ) 4.25 , d ) 5.25 , e ) 0.25
Example Output: e

Example Input: Problem: if 48 machine can finish a job in 80 days , then how many more machines would be needed to finish the job in one - fifth less time ? 
Options: a ) a . 4 , b ) b . 8 , c ) c . 10 , d ) d . 12 , e ) e . 16
Example Output:
d