Maribel is on a jury and she is already convinced that the defendant in the case is not guilty. She listens very attentively to everything the defense attorneys have to say, but she tends to pay less attention when the prosecution is presenting evidence. In this instance, Maribel is showing evidence of:

A. a confirmation bias

B. the framing effect

C. functional fixedness

D. the availability heuristic

Answer: A. A confirmation bias

Explanation: Since Maribel is already convinced that the defendant is not guilty, she seeks proof, or rather, confirmation of her opinion, feeling, conviction, etc. That is why she carefully listens to what the defense lawyer has to say, while paying less attention to the prosecutor's statement. This means that Maribel has a certain bias towards the accused and seeks confirmation of her bias, that is, her conviction that the accused is not guilty.

The term confirmation bias in psychology means favouring information that confirms one's opinion (bias), while ignoring information that states the opposite. This means that confirmation bias is, in fact, a kind of cognitive bias, because Maribel has already cognitively perceived (decided) the accused for some reason not guilty, although may exists evidence to the contrary.