Final answer:
The electric field inside a conducting sphere placed in an external uniform electric field is zero, as charges redistribute themselves on the surface to cancel out the external field within the conductor.
Step-by-step explanation:
The question you asked relates to the behavior of electric fields in and around conductors when placed in an external uniform electric field. According to the properties of a conductor in electrostatic equilibrium, the electric field inside a conducting sphere is zero. This is because excess charges on a spherical conductor repel each other and move until they are evenly distributed on the surface of the conductor, leaving the interior field-free.
This principle applies regardless of the presence of an external field, as the charges on the surface of the conductor will rearrange themselves to cancel out the external field within the conductor. Therefore, the correct statement is: 1) The electric field inside the sphere is zero. This is fundamentally different from a charged non-conducting sphere where the electric field varies inside the sphere.