When installing a new kitchen sink faucet, a plumber notices that the existing supply lines are corroded and show signs of minor leakage near the shut-off valves. What is the most professional and code-compliant course of action?

Question: When installing a new kitchen sink faucet, a plumber notices that the existing supply lines are corroded and show signs of minor leakage near the shut-off valves. What is the most professional and code-compliant course of action?

Answer options: ✅ Replace the corroded supply lines and shut-off valves.

• Tighten the existing supply line connections and observe for leaks.
• Apply thread sealant over the corroded areas to temporarily stop the leaks.
• Install the new faucet but advise the homeowner to monitor the old supply lines.

Correct answer: Replace the corroded supply lines and shut-off valves.

Explanation: Corroded and leaking supply lines and shut-off valves are a significant plumbing defect and must be replaced to ensure system integrity and prevent future water damage. Simply tightening or applying sealant is a temporary fix and does not address the underlying issue, and leaving them in place is irresponsible.