The electric field at a point situated at a distance d from straight charged conductor is

The electric field at a point situated at a distance d from a straight charged conductor is inversely proportional to d. This is because the electric field is created by the charges on the conductor, and the further away you are from the conductor, the weaker the electric field will be.

Option A is incorrect because the electric field is not proportional to d. Option B is correct because the electric field is inversely proportional to d. Option C is incorrect because the electric field is not inversely proportional to d squared. Option D is incorrect because the electric field is not none of the above.