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

Ex Input:
Problem: in gabriel ' s sheep herd , every sheep has either fleas or lice or both . half of the sheep have lice , and 84 sheep have both pests . if 94 sheep have lice , how many sheep have only fleas ? 
Options: a ) 10 , b ) 20 , c ) 84 , d ) 94 , e ) 178

Ex Output:
a


Ex Input:
Problem: in a class , 30 students pass in english and 20 students in math , while some students among these pass in both . how many more students do only english as compared to those doing only maths ? 
Options: a ) 10 , b ) 15 , c ) 20 , d ) 25 , e ) indeterminate

Ex Output:
a


Ex Input:
Problem: a man invests some money partly in 12 % stock at 108 and partly in 10 % stock at 60 . to obtain equal dividends from both , he must invest the money in the ratio : 
Options: a ) 3 : 4 , b ) 3 : 2 , c ) 4 : 5 , d ) 16 : 15 , e ) none

Ex Output:

b