Final answer:
The nurse should encourage the client to perform hip flexion exercises independently.
Step-by-step explanation:
The nurse should include the instruction to encourage the client to perform hip flexion exercises independently to the assistive personnel (AP) regarding care for a client following a total hip arthroplasty. These exercises help maintain joint mobility and strengthen the hip muscles. Option B, 'Keep the affected hip in a flexed position,' is not recommended as it can lead to contractures and hinder healing. Option C, 'Assist the client to a standing position every 2 hours,' is important for preventing complications but is not specific to the client's hip care. Option D, 'Apply a heating pad to the affected hip to relieve pain,' is not recommended as heat can increase swelling and discomfort.