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

Example Input: Problem: how many of the positive factors of 42 are not factors of 56 ? 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5
Example Output: c

Example Input: Problem: a student committee on academic integrity has 90 ways to select a president and vice president from a group of candidates . the same person can not be both president and vice president . how many candidates are there ? 
Options: a ) 7 , b ) 8 , c ) 9 , d ) 10 , e ) 11
Example Output: d

Example Input: Problem: two numbers are in the ratio 3 : 4 . if their l . c . m . is 36 . what is sum of the numbers ? 
Options: a ) 21 , b ) 56 , c ) 76 , d ) 84 , e ) 85
Example Output:
a