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: if a ( a + 2 ) = 99 and b ( b + 2 ) = 99 , where a ≠ b , then a + b = 
Options: a ) - 2 , b ) - 5 , c ) - 8 , d ) - 10 , e ) - 12

Output: a


Input: Consider Input: Problem: the average of first seven prime numbers which are between 30 and 70 is 
Options: a ) 35.4 , b ) 42 , c ) 44.4 , d ) 57 , e ) 67

Output: c


Input: Consider Input: Problem: a rope of which a calf is tied is increased from 12 m to 18 m , how much additional grassy ground shall it graze ? 
Options: a ) 1217 , b ) 1219 , c ) 1210 , d ) 565.7 , e ) 1312


Output: d