At first glance you might think the answer is (c), since 8% times 40% is 3.2%. But that is true only if P(A) and P(B) are independent, and they don't say whether the events are independent or not. If not then the anwer could be higher than 3.2%. Here's an example of events that aren't independent: if P(A) is the probability of a randomly selected person being female = 50%, and P(B) is the probability of a randomly selected person being a mother = 30%, then the probability that both A and B occur is 30%, not 50% x 30%.