Final answer:
Among the given options, 'anger and resistance' indicate a regressive client response to the termination of a therapeutic relationship, reflecting a return to earlier behavior patterns.
Step-by-step explanation:
The regressive client response to the termination of a therapeutic relationship is characterized by behaviors that indicate a move backward in development or a return to earlier patterns of behavior. Amongst the options given, anger and resistance most accurately represents a regressive response. This can be understood within the framework of defense mechanisms, in which regression is a retreat to an earlier developmental stage when faced with unacceptable thoughts or impulses, an example of which may be not wanting to accept the end of therapy.
In contrast, acceptance and gratitude, assertiveness and self-awareness, and anxiety and fear do not necessarily signify regression. Acceptance and gratitude indicate a positive and mature processing of the therapeutic relationship ending, while assertiveness and self-awareness may demonstrate personal growth that has resulted from therapy. Anxiety and fear, while not ideal, could represent normal apprehension about losing support rather than a regress to an earlier developmental stage.