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: 5 / 4 of all married couples have more than one child . 2 / 5 of all married couples have more than 3 children . what fraction of all married couples have 2 or 3 children ? 
Options: a ) 1 / 5 , b ) 1 / 4 , c ) 17 / 20 , d ) 3 / 5 , e ) it can not be determined from the given information .

Ex Output:
c


Ex Input:
Problem: what is the next number : 2 , 17 , 257 , __ 
Options: a ) 2977 , b ) 3837 , c ) 4097 , d ) 4847 , e ) 5387

Ex Output:
c


Ex Input:
Problem: andrew travelling to 7 cities . gasoline prices varied from city to city . $ 1.75 , $ 1.61 , $ 1.79 , $ 2.11 , $ 1.96 , $ 2.09 , $ 1.85 . what is the median gasoline price ? 
Options: a ) $ 1 , b ) $ 1.85 , c ) $ 1.92 , d ) $ 2.13 , e ) $ 2.15

Ex Output:

b