An interviewer is asking people on the street questions about the mayor of a hypothetical town. He tells them that the new mayor has an advanced degree and has specialized in women's and gender issues. The interviewer presents them with two situations and asks which one of them is more probable. He asks them if it is more probable that the mayor formerly worked in academics, or if it is more probable that the mayor is a female who has a degree in law. If the interviewees pick the second situation, which error in judgment are they committing?

a) conjunction fallacy
b) availability bias
c) sunk-cost fallacy
d) optimism bias