In a box of 9 pens, a total of 2 are defective. If a customer buys 2 pens selected at random from the box, what is the probability that neither pen will be defective? Choices.
A) 4 / 7
B) 5 / 9
C) 6 / 11
D) 7 / 12
E) 8 / 15

Rationale: "# defective pens = 2 # good pens = 7 probability of the 1 st pen being good = 7 / 9 probability of the 2 nd pen being good = 6 / 8 total probability = 7 / 9 * 6 / 8 = 7 / 12 the answer is d ."
Answer: D