Which of the following statements are correct?

A. Inside a conductor, the electrostatic field is zero.
B. Electric field at the surface of a charged conductor does not depend on its surface charge density.
C. The interior of a charged conductor can have no excess charge in the static situation.
D. At the surface of a charged conductor, the electrostatic field must be normal to the surface at every point.
E. The electrostatic potential is zero everywhere inside a charged conductor.

Choose the correct answer from the options given below:

We examine each statement about electrostatics in conductors.

A. Inside a conductor, the electrostatic field is zero.
In electrostatic equilibrium the free charges in a conductor have moved until the net electric field inside cancels. Any non‑zero field would cause charges to continue moving, contradicting static conditions. Hence the field inside a conductor is indeed zero. This statement is correct.

B. Electric field at the surface of a charged conductor does not depend on its surface charge density.
The normal component of the electric field just outside the surface is given by $E\_n\; =\; \backslash frac\{\backslash sigma\}\{\backslash varepsilon\_0\}$, where $\backslash sigma$ is the surface charge density and $\backslash varepsilon\_0$ is the vacuum permittivity. Therefore the field directly depends on the amount of charge per unit area. The statement is incorrect.

C. The interior of a charged conductor can have no excess charge in the static situation.
Excess charge on a conductor repels each other and moves to the outer surface to minimize the system’s energy. In static equilibrium no net charge remains in the interior; all excess charge resides on the surface. This statement is correct.

D. At the surface of a charged conductor, the electrostatic field must be normal to the surface at every point.
The tangential component of the electric field at the surface would cause surface charges to drift, violating electrostatic equilibrium. Consequently the field can only have a component perpendicular (normal) to the surface. The statement is correct.

E. The electrostatic potential is zero everywhere inside a charged conductor.
While the potential is constant throughout the interior of a conductor (because $\backslash mathbf\{E\}=0$), its value is not forced to be zero; it equals the potential of the surface, which may be any constant determined by external influences. Hence this statement is incorrect.

Collecting the true statements we have A, C and D only.