Official GRE quant practice book: MIxed practice set 2 (question 17, pg.192)

  1. Of the 40 specimens of bacteria in a dish, 3 specimens have a certain trait. If 5 specimens are to be selected from the dish at random and without replacement, which of the following represents the probability that only 1 of the 5 specimens selected will have the trait?

A. (5/1)/(40/3)
B. (5/1)/(40/5)
C. (40/3)/(40/5)
D. ((3/1)(37/4))/(40/3)
E. ((3/1)(37/4))/(40/5)

Can you guys just help with your thought process and how you would attack this question?

https://www.youtube.com/watch?v=X1p_NKUawYE
Vince explains this question very well