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 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
Example Output: c

Example Input: Problem: a confectioner decides to sell all of his pastry due to the coming holiday . his pastry goods are equally divided among a group of 28 regular customers . if only 49 customers come to the bakery , each one will receive 6 less pastry goods . how much pastry does the confectioner needs to sell ?
Options: a ) 392 , b ) 412 . , c ) 432 . , d ) 502 , e ) 522
Example Output: a

Example Input: Problem: find the numbers which are in the ratio 3 : 2 : 3 such that the sum of the first and the second added to the difference of the third and the second is 24 ?
Options: a ) 4 , 3,22 , b ) 4 , 4,22 , c ) 9 , 3,32 , d ) 9 , 6,12 , e ) 18 , 12,18
Example Output:
e