A box contains nine bulbs out of which 4 are defective. If four bulbs are chosen at random, find the probability that all the four bulbs are defective.	Choose the correct choice from the following answers: A) 62/63 B) 125/126 C) 1/63 D) 1/42 E) 1/126
Answer: Option E   Out of nine, five are good and four are defective. Required probability = â´câ‚„/â¹câ‚„ = 1/126
<result>E</result>
A box contains nine bulbs out of which 4 are defective. If four bulbs are chosen at random, find the probability that all the four bulbs are defective.