In a box of 11 pencils, a total of 2 are defective. If a customer buys 3 pencils selected at random from the box, what is the probability that neither pencils will be defective?  Choose the correct choice from the following.
A) 1 / 25  B) 28 / 55  C) 2 / 35  D) 2 / 55  E) 1 / 75

Rationale: "first , there are 9 c 3 ways you can select 3 good pencils from 4 good ones . second , there are 11 c 3 ways you select 3 pencils from 6 ones in the box . then , the probability that neither pen will be defective is : 9 c 3 / 11 c 3 = 84 / 165 = 28 / 55 answer is b"
Answer: B