In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: the product of two numbers is 2028 and their h . c . f is 13 . the number of such pairs is : 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5

Ex Output:
b


Ex Input:
Problem: ( 700 + 200 ) ã — 4 ã — ( 4 + 2 ) = ? 
Options: a ) 24500 , b ) 21600 , c ) 36600 , d ) 22400 , e ) 12500

Ex Output:
b


Ex Input:
Problem: if 15 students in a class average 80 % on an english exam and 10 students average 90 % on the same exam , what is the average in percent for all 25 students ? 
Options: a ) 83 % , b ) 83 1 ⁄ 2 % , c ) 84 % , d ) 85 % , e ) 86 2 ⁄ 3 %

Ex Output:

c