Answer:
A. a man believing that dietary change would not reduce his risk of a heart attack
Explanation:
A perceived barrier is an individual's estimation of how challenging social, personal, environmental, and economic obstacles are to reach a desired goal. This barrier prevents the person to engage in health-promoting behavior, therefore the example that best exemplifies this barrier is a man believing that dietary change would not reduce his risk of a heart attack, where the perceived barrier is the dietary change not helping and the desired goal is to reduce the risk of a heart attack.
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