The correct option is A 5 ohm m
Resistivity is a property of the material. That’s what I was trying to convey through that hint. Potential difference across a conductor may change its current but can’t change its resistivity.
BTW just that you should know: there are some factors which alter the basic nature of a material and may change such “intrinsic” or “Intensive” property. For example, temperature but potential difference, surely not.