In this task, you need to provide the correct option for a given problem from the provided options.

Input: Consider Input: Problem: what is the units digit of 31 ! + 50 ! + 2 ! + 3 ! ? 
Options: a ) 0 , b ) 2 , c ) 4 , d ) 6 , e ) 8

Output: e


Input: Consider Input: Problem: if m = 3 ^ n , what is the greatest value of n for which m is a factor of 16 ! 
Options: a ) 8 , b ) 10 , c ) 6 , d ) 14 , e ) 16

Output: c


Input: Consider Input: Problem: 3 years ago , the ratio of ages of p and q was 4 : 3 . 6 years from now , the ratio of their ages will be 7 : 6 . what is p ' s age at present ? 
Options: a ) 9 , b ) 12 , c ) 15 , d ) 18 , e ) 21


Output: c