The correct answer is option 3, which states that the electric field inside a perfectly conducting hollow object is zero. This is because a perfectly conducting material has free charges that are able to move freely. When an external electric field is applied to the material, the free charges redistribute themselves on the surface of the material in such a way that the electric field inside the material becomes zero.

This can be understood by considering Gauss`s law, which states that the electric flux through a closed surface is proportional to the total charge enclosed by the surface. In the case of a hollow conducting object, the charges inside the object will redistribute themselves in a way that the electric field they create cancels out the external electric field. As a result, the net charge inside the object is zero, and therefore, the electric field inside is also zero.

It is important to note that this conclusion holds regardless of the shape of the object. Whether the object is spherical, cylindrical, or any other shape, as long as it is perfectly conducting, the electric field inside will be zero.