Instructions: In this task, you need to provide the correct option for a given problem on probability from the provided options.
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 blue ? 
Options: a ) 20 / 969 , b ) 20 / 875 , c ) 21 / 876 , d ) 3 / 512 , e ) 2 / 9
Output:
a