A nurse is caring for a client who has posttraumatic stress disorder (PTSD) after being physically assaulted. The client is unable to recall any details of the event. Which of the following defense mechanisms should the nurse recognize that the client is displaying?

A. Dissociation: Dissociation is a defense mechanism in which a person disconnects from painful or traumatic memories, thoughts, or feelings. In PTSD, clients may exhibit dissociation by being unable to recall details of a traumatic event, which serves to protect them from psychological distress. B. Rationalization: Rationalization involves creating logical or socially acceptable explanations for behaviors or feelings that are actually driven by unconscious impulses. It does not involve memory loss or inability to recall a traumatic event. C. Undoing: Undoing is a defense mechanism where a person tries to “reverse” or negate a previous thought, action, or feeling, often through symbolic behavior. It does not explain memory loss related to trauma. D. Reaction formation: Reaction formation occurs when a person behaves in a way that is opposite to their unacceptable thoughts or feelings. It does not involve memory gaps or inability to recall traumatic events.