A nurse is caring for a client who has borderline personality disorder. Which of the following defense mechanisms is commonly used by clients who have this disorder and has the potential to create division amongst the healthcare team?

A. Splitting is a defense mechanism in which the client perceives people or situations as all good or all bad, with no middle ground. This can create conflict and division among healthcare team members, as the client may idealize one staff member while devaluing another, potentially disrupting team cohesion and continuity of care. B. Regression involves reverting to earlier developmental behaviors (e.g., childish or dependent actions) under stress, but it does not typically cause division among staff. C. Denial is the refusal to acknowledge reality or facts of a situation. While it can affect treatment adherence, it does not usually create interpersonal conflict among caregivers. D. Reaction formation is the expression of behavior that is opposite to true feelings (e.g., acting overly friendly toward someone the client dislikes). While it may be confusing, it generally does not have the same divisive effect on the healthcare team as splitting.