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# P.D. between two points in a wire is.... watch

1. I eliminated A but I am unable to eliminate either of the other options to arrive conclusively at the answer : C
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2. I reckon it would be C .

Units of Power is in Watts or V A since P=IV

C mentions the Ratio of power to Current .

I just looked at the units and concluded that V A : A would just give V ( as the Amps symbols would cancel out), which is the unit for the potiential difference across the wire.
3. We know that an expression for the power generated in the wire is P = VI. So rearranging, we get V = P/I, which means it roughly needs to have the dimensions of joules/coulomb.

If you take the ratio of energy/current or power/charge, you don't get the same thing as before.

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