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

Ex Input:
Problem: a coin is tossed 3 times . what is the probability of getting exactly 2 heads ? 
Options: a ) 1 / 2 , b ) 1 / 4 , c ) 3 / 8 , d ) 5 / 8 , e ) 3 / 16

Ex Output:
c


Ex Input:
Problem: an urn contains 5 red , 6 blue and 8 green balls . 3 balls are randomly selected from the urn , find the probability that the drawn ball are 2 blue and 1 red ? 
Options: a ) 25 / 323 , b ) 21 / 969 , c ) 28 / 989 , d ) 74 / 879 , e ) 23 / 589

Ex Output:
a


Ex Input:
Problem: there is a 50 % chance jen will visit chile this year , while there is a 25 % chance that she will visit madagascar this year . what is the probability that jen will visit either chile or madagascar this year , but not both ? [ / b ] 
Options: a ) 25 % , b ) 50 % , c ) 62.5 % , d ) 63.5 % , e ) 75 %

Ex Output:

b