What are two examples of properties of materials that are crucial for semiconductor functionality?

The correct answer highlights two fundamental properties of materials that are critical for the functionality of semiconductors: conductivity and valence electrons.

Conductivity refers to a material's ability to conduct electricity, which is essential for semiconductors that must manage the flow of electrical current in electronic devices. Semiconductors are unique because they have conductivity that is between that of insulators and conductors, allowing them to be manipulated to turn on or off in response to electrical signals.

Valence electrons are the electrons in the outer shell of an atom that participate in chemical bonding and electrical conduction. In semiconductors, the arrangement and behavior of these valence electrons are crucial. For instance, the presence of impurities (doping) can modify the number of free charge carriers (electrons or holes) in a semiconductor, thereby enhancing its conductivity and allowing for control in electronic applications.

The other options do not address properties that directly impact the behavior of semiconductors. Density, mass, weight, color, texture, and cohesion are generally not relevant when discussing semiconductor function, as they do not directly influence electrical conduction or the manipulation of electrons in semiconductor materials.