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 sum of all the integers k such that – 25 < k < 24 is 
Options: a ) 0 , b ) - 2 , c ) - 25 , d ) - 49 , e ) - 47
Example Output: e

Example Input: Problem: a man purchased 3 blankets @ rs . 100 each , 6 blankets @ rs . 150 each and two blankets at a certain rate which is now slipped off from his memory . but he remembers that the average price of the blankets was rs . 150 . find the unknown rate of two blankets ? 
Options: a ) a ) 300 , b ) b ) 350 , c ) c ) 450 , d ) d ) 470 , e ) e ) 500
Example Output: a

Example Input: Problem: in 10 years , a will be twice as old 5 as b was 10 years ago . if a is now 7 years older than b , the present age of b is 
Options: a ) 35 , b ) 37 , c ) 39 , d ) 41 , e ) 42
Example Output:
b