Before any work on electrical or electronic equipment is performed, which of the following precautions should be carried out?

Correct Answer: Option C — Secure and tag the supply circuit breaker in the open position.

Lockout/Tagout (LOTO) procedures are mandatory for personnel safety. Securing and tagging the supply breaker in the open position ensures the circuit remains de-energized, preventing accidental re-energization while work is performed. This adheres to standard marine safety protocols and IEEE 45 guidelines for electrical maintenance and equipment repair.