A client recently diagnosed with cancer continues to miss follow-up appointments and states, "The doctors must have made a mistake—there’s no way I’m that sick." According to Freud’s psychoanalytic theory, which defense mechanism is the client most likely using?

Choice A reason: Rationalization involves creating logical explanations to justify behavior or feelings. In this case, the client is not justifying but outright rejecting the diagnosis, so this does not apply. Choice B reason: Regression occurs when an individual reverts to earlier developmental behaviors, such as childish actions, to cope with stress. The client is not reverting to earlier behaviors but refusing to accept reality. Choice C reason: Denial is the refusal to accept reality or facts, blocking external events from conscious awareness. The client’s insistence that the diagnosis is a mistake demonstrates denial, making this the correct defense mechanism. Choice D reason: Projection occurs when a person attributes their unacceptable thoughts or feelings to someone else. The client is not attributing their illness to others but rejecting its existence altogether.