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

Ex Input:
Problem: if 30 % of the 880 students at a certain college are enrolled in biology classes , how many students at the college are not enrolled in a biology class ? 
Options: a ) 620 , b ) 630 , c ) 616 , d ) 600 , e ) 650

Ex Output:
c


Ex Input:
Problem: in a certain alphabet , 10 letters contain a dot and a straight line . 24 letters contain a straight line but do not contain a dot . if that alphabet has 40 letters , all of which contain either a dot or a straight line or both , how many letters contain a dot but do not contain a straight line ? 
Options: a ) 6 , b ) 8 , c ) 14 , d ) 20 , e ) 28

Ex Output:
a


Ex Input:
Problem: the contents of two vessels containing copper and tin in the ratio 2 : 3 and 5 : 7 are mixed in the ratio 3 : 5 . the resulting mixture will have copper and tin in the ratio ? 
Options: a ) 210 : 283 , b ) 312 : 433 , c ) 178 : 213 , d ) 197 : 283 , e ) 145 : 256

Ex Output:

d