Final answer:
The nurse should place a mask on the client to limit the spread of microorganisms into the surgical wound, ensuring that the sterile field is maintained and reducing the risk of contamination.
Step-by-step explanation:
When preparing a sterile field, it is important that the nurse takes measures to prevent the spread of infection due to the client coughing and sneezing near the surgical wound. The most appropriate action would be to place a mask on the client to limit the spread of microorganisms into the surgical wound. This reduces the risk of contamination and helps maintain the integrity of the sterile field. Other key practices include enforcing stringent hand hygiene, using gloves, and proper disposal of tissues to prevent surface and equipment contamination. It is also imperative to instruct clients on the importance of covering their mouth and nose when sneezing and to always follow strict protocols for infection control.