Fuses and ___ are designed to protect equipment.

• A. Relays
• B. Circuit breakers
• C. Transformers
• D. Capacitors

Answer: (B)

Fuses and circuit breakers are protective devices that interrupt current to prevent damage from overloads or faults. A fuse works by melting its metal link when current is too high, breaking the circuit. A circuit breaker performs the same protection but can be reset after tripping, so it’s reusable. Relays control other parts of a circuit, transformers change voltage levels, and capacitors store energy or smooth power—not primarily as protective interruptors. So the missing term is circuit breakers.