If you known material that conducts electricity and heat well, what kind of substance would it be?

A. It could be a metal or a nonmetal
B. It must be a metalloid
C. It must be a metal
D. It must be a nonmetal

C. It must be a metal

C. It must be a metal.

C. It must be a metal.

Explanation:
Material that conducts electricity and heat well are called conductors. Metals are known to be good conductors of electricity and heat due to their unique atomic structure. In metals, the valence electrons (the electrons involved in bonding) are loosely held and are able to move freely throughout the material. This movement of electrons allows for efficient transfer of both electricity and heat.

To determine the answer to this question, it is important to understand the properties of metals, nonmetals, and metalloids. Metals are generally malleable, ductile, and have a lustrous appearance. Nonmetals, on the other hand, are poor conductors of electricity and heat. Metalloids, also known as semimetals, have properties that are intermediate between metals and nonmetals but are not necessarily good conductors of heat and electricity. Therefore, the correct answer is C. It must be a metal.