单选题Since fuse elements are made of zinc or any alloy of tin and lead, the melting point of the fuse element must be （）.Ahigher than that of copperBlower than that of copperCequal to that of copperDreached when the conductor it is protecting becomes white hot
单选题
Since fuse elements are made of zinc or any alloy of tin and lead, the melting point of the fuse element must be （）.
A
higher than that of copper
B
lower than that of copper
C
equal to that of copper
D
reached when the conductor it is protecting becomes white hot
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