A box contains 25 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 Choices
A) 3 / 10	B) 7 / 19	C) 12 / 19	D) 21 / 95	E) none

Rationale: "solution p ( none is defective ) = 21 c 2 / 25 c 2 = 7 / 10 p ( at least one is defective ) = ( 1 - 7 / 10 ) = 3 / 10 . answer a"
Answer: A