Final answer:
The nurse should advise a client with Raynaud's phenomenon to wear extra-warm clothing during cold exposure and to quit smoking, possibly using nicotine gum as an aid.
Step-by-step explanation:
The correct instruction a nurse should discuss with a client diagnosed with Raynaud's phenomenon is c. Wear extra-warm clothing during cold exposure. Raynaud's phenomenon is a condition where the blood vessels in the fingers and toes spasm, leading to reduced blood flow. This is often triggered by cold temperatures or stress. Wearing warm clothing helps prevent these spasms by keeping the body temperature stable. It is also vital for individuals with Raynaud's to avoid smoking, as nicotine can exacerbate blood vessel constriction, thereby worsening the symptoms of Raynaud's phenomenon. Therefore, using nicotine gum to help quit smoking would also be beneficial.