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 marks of a class of 30 students is 40 and that of another class of 50 students is 60 . find the average marks of all the students ? 
Options: a ) 82.5 , b ) 52.9 , c ) 52.2 , d ) 52.5 , e ) 52.7
Example Output: d

Example Input: Problem: the sum of three consecutive multiples of 3 is 108 . what is the largest number ? 
Options: a ) 36 , b ) 39 , c ) 33 , d ) 30 , e ) 42
Example Output: b

Example Input: Problem: a man distributed rs . 100 equally among his friends . if there had been 5 more friends , each would have received one rupee less . how many friends had he ? 
Options: a ) 20 , b ) 25 , c ) 30 , d ) 35 , e ) 40
Example Output:
b