When caring for a client with pneumonia, what intervention is most effective in preventing the spread of infection?
Correct Answer: D
Rationale: The correct answer is D because performing hand hygiene before and after client contact is crucial in preventing the spread of infection in pneumonia. This intervention helps in reducing the transmission of infectious agents from one client to another and from surfaces to clients. It is a fundamental infection control measure that minimizes the risk of spreading pathogens. Option A is important for treating the infection but does not directly prevent its spread. Option B is a good practice to contain respiratory secretions but may not be as effective as hand hygiene. Option C isolates the client but does not address the primary mode of transmission through contaminated hands.