单选题Copper is often used as an electrical conductor because it （）.Ahas high resistance at low temperaturesBhas a highly polished surfaceCis able to pass current with little oppositionDholds insulation together well
单选题
Copper is often used as an electrical conductor because it （）.
A
has high resistance at low temperatures
B
has a highly polished surface
C
is able to pass current with little opposition
D
holds insulation together well
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