Ahard, crystalline solid with a high melting point does not conduct electricity in any phase. this solid is most likely
(a) an ionic solid.
(b) a metallic solid.
(c) a molecular solid.
(d) a network covalent solid.

d. a network covalent solid.

Explanation:

A network covalent solid -

In these type of solids , the atoms are connected to each other via covalent bonds , its consists of large number of atoms connected in a three dimensional arrangement.

Hence, from the given information of the question,

The correct term from the given options is d. a network covalent solid.

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."

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