单选题A circuit breaker differs from a fuse in that a circuit breaker （）.Amelts and must be replacedBis enclosed in a tube of insulating material with metal ferrules at each endCgives no visual indication of having opened the circuitDtrips to break the circuit and may be reset
单选题
A circuit breaker differs from a fuse in that a circuit breaker （）.
A
melts and must be replaced
B
is enclosed in a tube of insulating material with metal ferrules at each end
C
gives no visual indication of having opened the circuit
D
trips to break the circuit and may be reset
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