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: x varies inversely as square of y . given that y = 3 for x = 1 . the value of x for y = 7 will be equal to : 
Options: a ) 3 , b ) 6 , c ) 1 / 9 , d ) 1 / 3 , e ) 9 / 49
Example Output: e

Example Input: Problem: the product of a and b is equal to 12 more than twice the sum of a and b . if b = 10 , what is the value of b - a ? 
Options: a ) 2 , b ) 5 , c ) 7 , d ) 6 , e ) 35
Example Output: d

Example Input: Problem: the average of first 17 even numbers is ? 
Options: a ) 10 , b ) 11 , c ) 18 , d ) 20 , e ) 24
Example Output:
c