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: the average of first seven prime numbers which are between 30 and 70 is
Options: a ) 35.4 , b ) 42 , c ) 44.4 , d ) 57 , e ) 67
Example Output: c

Example Input: Problem: if 5400 mn = k ^ 4 , where m , n , and k are positive integers , what is the least possible value of m + 2 n ?
Options: a ) 11 , b ) 18 , c ) 20 , d ) 25 , e ) 40
Example Output: e

Example Input: Problem: how many positive integers less than 254 are multiple of 4 but not multiples of 6 ?
Options: a ) 20 , b ) 31 , c ) 42 , d ) 43 , e ) 64
Example Output:
d