Bill is a retired aircraft mechanic, who has agreed to talk to a group of high school students about the early days of commercial aviation. bill is concerned that any slip in his memory will confirm the belief that all older people are forgetful. because he is anxious and preoccupied about possible memory lapses, bill actually does have problems with his memory. this illustrates that

Negative stereotype enforcing self fulfilling quality.

Explanation:

According to psychologist Claude Steele, people who are exposed to negative stereotype develops self-fulling qualities. He has evident researches to prove that when an individual's qualities are assessed he feel stereotype threat. The feeling of being judged develops anxiety which results in lower performance of the individual.

As per the question, Bill's stereotype about the memory loss of older people actually resulted in memory loss.

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