Answer :
Final answer:
The patient is using denial as a defense mechanism by rejecting a diagnosis of diabetes. Other defense mechanisms like projection and regression are also explained.
Explanation:
Denial is the defense mechanism being used when a patient states, 'The lab must have mixed up the samples, I don't have diabetes.' This defense mechanism involves not accepting the truth or lying to oneself, such as denying a diagnosis like diabetes.
Projection: a defense mechanism in which a person attributes their unacceptable thoughts onto others. For example, accusing someone else of having feelings that they themselves are unwilling to acknowledge.
Regression: an individual acts much younger than their age, like reverting to an earlier developmental stage under stress. For instance, a person behaving like a child when faced with a challenging situation.
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