Q: An urn contains 6 red, 5 blue and 2 green marbles. If 2 marbles are picked at random, what is the probability that both are red?
Options:
(A) 6/13
(B) 5/26
(C) 6/26
(D) 9/26
(E) 10/27
A: (B)
Explain how we arrive at this answer: 
Explanation: Option(B) is correct
P(Both are red), 6C2/13C2 = 5/26