Which of the following statements is true?

Options

A. A solid is an insulator or semiconductor, if its conduction band is partially filled
B. A solid is necessarily an insulator, if its conduction band is empty
C. A solid is necessarily a semiconductor, if its conduction band is empty
D. A solid is a conductor, if its conduction band is partially filled

Answer

D

Explanation

For an insulator, conduction band must be empty. For a semiconductor, conduction band is partially filled. For a conductor, conductive band is partially filled. (Note: option 2, is also correct).