A box contains 21 electric bulbs, out of which 4 are defective. Two bulbs are chosen at random from this box. The probability that at least one of these is defective is Choose the correct choice from the following choices
A) 4 / 19 B) 7 / 19 C) 12 / 19 D) 21 / 95 E) 31 / 88

Rationale: "solution p ( none is defective ) = 17 c 2 / 21 c 2 = 57 / 88 . p ( at least one is defective ) = ( 1 - 57 / 88 ) = 31 / 88 . answer e"
Answer: E