Which option correctly matches the mode of transmission with the appropriate PPE and room placement?

• A. Airborne precautions for TB and measles require a respirator; Droplet precautions for influenza and mumps require a surgical mask; Contact precautions for MRSA and C. diff require gloves and gown.
• B. Airborne precautions require a surgical mask; Droplet precautions require an N95 respirator; Contact precautions require gloves.
• C. Airborne precautions require gloves and gown; Droplet precautions require a negative-pressure room; Contact precautions require no special PPE.
• D. Airborne precautions require no PPE; Droplet precautions require a gown; Contact precautions require a respirator.

Answer: (A)

The guiding idea is that how a pathogen spreads determines what PPE and room setup protect both patient and staff. Airborne spread involves tiny particles that stay suspended in air, so protection requires a respirator (N95 or higher) and placement in a negative‑pressure room to prevent contaminated air from circulating. Droplet spread involves larger particles that travel short distances, so a surgical mask is appropriate for close contact, and a standard room is typically sufficient. Contact spread occurs through direct or indirect contact, so gloves and a gown are the main protections to prevent contaminating surfaces and yourself.

The best option matches this pattern: airborne precautions use a respirator, droplet precautions use a surgical mask, and contact precautions use gloves and a gown, with the airborne scenario ideally involving a negative‑pressure room. The other options mix up which PPE goes with which transmission mode or omit the room‑placement aspect, which is why they’re not correct.