Subject: mathqa
Question: in a box of 11 pens , a total of 3 are defective . if a customer buys 2 pens selected at random from the box , what is the probability that neither pen will be defective ?
Option: 
A: 19 / 33
B: 7 / 11
C: 28 / 55
D: 3 / 5
Answer: C