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: if - 3 x + 2 y = 28 and 3 x + 6 y = 84 , what is the product of x and y ? 
Options: a ) 264 . , b ) 428 , c ) 0 , d ) 462 , e ) 642
Example Output: c

Example Input: Problem: the ratio of the ages of mini and minakshi is 4 : 3 . the sum of their ages is 35 years . the ratio of their ages after 8 years will be 
Options: a ) 28 : 23 , b ) 6 : 11 , c ) 5 : 4 , d ) 3 : 5 , e ) 7 : 11
Example Output: a

Example Input: Problem: what is the sum of all digits for the number 10 ^ 29 - 41 ? 
Options: a ) 257 , b ) 242 , c ) 231 , d ) 202 , e ) 187
Example Output:
a