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: what is the next number 12 13 15 17 111 113 117 119 123 129 ? 
Options: a ) 154 , b ) 220 , c ) 129 , d ) 131 , e ) 224

Output: d


Input: Consider Input: Problem: a number is doubled and 5 is added . if the resultant is trebled , it becomes 123 . what is that number ? 
Options: a ) 12 , b ) 29 , c ) 27 , d ) 18 , e ) 99

Output: d


Input: Consider Input: Problem: how many multiples of 2 are there between 10 and 52 , 10 and 52 inclusive ? 
Options: a ) 27 , b ) 25 , c ) 24 , d ) 21 , e ) 22


Output: e