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'.

Input: Consider Input: Problem: exactly 3 / 5 of the people in the room are under the age of 21 , and exactly 5 / 13 of the people in the room are over the age of 65 . if the total number of the people in the room is greater than 50 and less than 100 , how many people in the room are under the age of 21 ? 
Options: a ) 21 , b ) 35 , c ) 39 , d ) 60 , e ) 42

Output: e


Input: Consider Input: Problem: what is the average of first 21 multiples of 6 ? 
Options: a ) a ) 66 , b ) b ) 77 , c ) c ) 79 , d ) d ) 81 , e ) e ) 82

Output: a


Input: Consider Input: Problem: the average of first 15 natural numbers is ? 
Options: a ) 7 , b ) 8 , c ) 9 , d ) 10 , e ) 11


Output: b