Final answer:
The nurse should instruct the receptionist to give the client with cough and fever a mask as soon as they arrive at the clinic to prevent the spread of infection, and to prepare for isolating the client from others.
Step-by-step explanation:
The appropriate action would be to give the client a mask as soon as they arrive at the ambulatory care clinic. This is because the client's symptoms of cough and fever could potentially be due to an infectious disease such as influenza, which is highly transmissible, especially in a healthcare setting. The receptionist should be informed to provide the client with a mask immediately upon arrival to minimize the risk of the infection spreading to others in the clinic.
It's also essential to isolate the client from other patients to prevent further transmission of the disease. This practice is based on the principle of infection control and aligns with the general expectations of not attending public places when symptomatic, as indicated in the reference material. Preparation for isolation may include designating a separate waiting area or quickly escorting the client to an examination room upon entry.