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

Ex Input:
Problem: two alloys a and b are composed of two basic elements . the ratios of the compositions of the two basic elements in the two alloys are 5 : 3 and 1 : 1 , respectively . a new alloy x is formed by mixing the two alloys a and b in the ratio 4 : 3 . what is the ratio of the composition of the two basic elements in alloy x ? 
Options: a ) 1 : 1 , b ) 2 : 3 , c ) 5 : 2 , d ) 4 : 3 , e ) 7 : 9

Ex Output:
d


Ex Input:
Problem: if x and y are both odd prime numbers andx < y , then how many different positive integer factors does 2 xyhave ? 
Options: a ) 3 , b ) 4 , c ) 6 , d ) 12 , e ) 8

Ex Output:
e


Ex Input:
Problem: how many of the positive factors of 33 are not factors of 45 ? 
Options: a ) 0 , b ) 1 , c ) 2 , d ) 3 , e ) 4

Ex Output:

c