What material primarily composes diatomaceous earth?

Diatomaceous earth is primarily composed of the skeletal remains of diatoms, which are tiny, aquatic organisms belonging to the algae family. These organism's cell walls are made of silica, which contributes to the unique properties of diatomaceous earth, making it a versatile material used in various applications like filtration, insulation, and as a natural pesticide. The composition of diatomaceous earth gives it a fine, coarse texture and allows it to absorb liquids and trap particles effectively.

The other options involve materials or substances that do not represent the primary composition of diatomaceous earth, which is specifically derived from the fossilized remains of diatoms that have accumulated over time. Understanding what diatomaceous earth is composed of provides insight into its uses and properties in different industries.