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: 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
Example Output: d

Example Input: Problem: the average temperature for monday , tuesday , wednesday and thursday was 48 degrees and for tuesday , wednesday , thursday and friday was 46 degrees . if the temperature on monday was 44 degrees . find the temperature on friday ?
Options: a ) 65 degrees , b ) 73 degrees , c ) 36 degrees , d ) 34 degrees , e ) 74 degrees
Example Output: c

Example Input: Problem: sandy bought 65 books for $ 1180 from one shop and 55 books for $ 860 from another shop . what is the average price that sandy paid per book ?
Options: a ) $ 13 , b ) $ 15 , c ) $ 17 , d ) $ 19 , e ) $ 21
Example Output:
c