Using solid-state physics could help understand which properties of solids? conductivity, melting point, color, and density conductivity, melting point, color, and viscosity diffusivity, melting point, color, and viscosity conductivity, melting point, diffusivity, and density

a => conductivity, melting point, color, and density.

Explanation:

The concept known as 'solid-state Physics'' is an important part of Physics and Chemistry; it is an important part of science in general. The concept is been studied and brought new aspects of science such as metallurgy, quantum mechanics, and many others. The studies discovered that atoms in solids have definite pattern in which each solids are being packed and this also is a cause for their properties for instance, how elastic these solids are, their magnetic properties and many more.

From the options given in the question above, When using the concept known as 'solid-state Physics'', the following can be use to understand how the properties of solids, they are:

[1]. conductivity,

[2]. melting point,

[3]. color, and

[4]. density.