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

Ex Input:
Problem: the number of sailors on a ship is 50 % more than the number of officers . the ratio of sailors to officers would be
Options: a ) 33 : 25 , b ) 47 : 20 , c ) 3 : 2 , d ) 22 : 25 , e ) 97 : 50

Ex Output:
c

Ex Input:
Problem: the ratio between the present ages of a and b is 3.5 : 3 respectively . the ratio between a ' s age 4 years ago and b ' s age 4 years hence is 1 : 1 . what is the ratio between a ' s age 4 years hence and b ' s age 4 years ago ?
Options: a ) 14 : 4 , b ) 13 : 0 , c ) 15 : 11 , d ) 13 : 12 , e ) 13 : 17

Ex Output:
c

Ex Input:
Problem: 10 different biology books and 8 different chemistry books lie on a shelf . in how many ways can a student pick 2 books of each type ?
Options: a ) 80 , b ) 160 , c ) 720 , d ) 1100 , e ) 1260

Ex Output:
e