John is a sexist who believes that women are incompetent business managers because they are "not temperamentally suited to the aggressive nature of the business world."

He notices every mistake his female managers make, but never seems to see their numerous successes. With each new mistake he notices, John becomes even more convinced of the incompetence of female managers. John's sexism is being maintained by the ______.
a. availability heuristic c. representativeness heuristic
b. idealized cognitive model d. confirmation bias

D