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

Ex Input:
Problem: a certain fraction has the same ratio to 1 / 33 , as 3 / 4 does to 7 / 11 . what is this certain fraction ? 
Options: a ) 1 / 14 , b ) 1 / 18 , c ) 1 / 21 , d ) 1 / 25 , e ) 1 / 28

Ex Output:
e


Ex Input:
Problem: a class has a ratio of 3 : 6 : 7 of children with red hair , blonde hair and black hair respectively . if the class has 9 kids with red hair , how many kids are there with black hair ? 
Options: a ) 7 , b ) 6 , c ) 9 , d ) 21 , e ) 63

Ex Output:
d


Ex Input:
Problem: find the probability in a group of 10 students sitting in a row , two of them always sit next to each other 
Options: a ) 0.5 , b ) 0.4 , c ) 0.3 , d ) 0.2 , e ) 0.1

Ex Output:

d