A cognitive psychologist would be most interested in a) how you decide which answer is correct for this question.
This is because cognitive psychology focuses on the mental processes involved in knowledge acquisition, decision-making, and problem-solving. Understanding how individuals process information, evaluate options, and arrive at conclusions is central to cognitive psychology. The other options, while relevant to psychology, pertain more to areas like neuroscience (b), developmental psychology (c), and clinical psychology (d), rather than the specific thought processes surrounding decision-making.