When bypass is used during maintenance, which precaution applies?

When bypass is used during maintenance, which precaution applies?

• A. Bypass must be used during maintenance to test the system.
• B. Bypass must be kept sealed and clearly labeled, and opened only during authorized maintenance and testing.
• C. Bypass must be left open during maintenance for quick testing.
• D. Bypass labeling is optional.

Answer: (C)