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

Ex Input:
Problem: water consists of hydrogen and oxygen , and the approximate ratio , by mass , of hydrogen to oxygen is 2 : 16 . approximately how many grams of oxygen are there in 162 grams of water ? 
Options: a ) 16 , b ) 72 , c ) 112 , d ) 128 , e ) 144

Ex Output:
e


Ex Input:
Problem: bag a contains red , white and blue marbles such that the red to white marble ratio is 1 : 3 and the white to blue marble ratio is 2 : 3 . bag b contains red and white marbles in the ratio of 1 : 4 . together , the two bags contain 26 white marbles . how many red marbles could be in bag a ? 
Options: a ) 1 , b ) 3 , c ) 4 , d ) 2 , e ) 8

Ex Output:
d


Ex Input:
Problem: a dog have birth to 12 puppies , 2 female and 10 male . what is the ratio of the female puppies to the male ? 
Options: a ) 1 / 5 , b ) 1 / 6 , c ) 1 / 10 , d ) 2 / 12 , e ) 1 / 8

Ex Output:

a