Asphalt is primarily composed of which of the following?

Asphalt is primarily composed of bitumens, which are a byproduct of the petroleum refining process. Bitumens are thick, sticky, and viscous substances that bind together the aggregates used in asphalt mixtures. This composition gives asphalt its unique properties, such as waterproofing, durability, and the ability to expand and contract with temperature changes. The presence of bitumens is what makes asphalt a preferred material for roofing and paving, as it provides excellent adhesion and flexibility.

Natural minerals, fibrous materials, and concrete composites are components that may be part of other construction materials but do not define the primary composition of asphalt. While some asphalt products may contain aggregates derived from natural minerals or fibrous materials for specific applications, the fundamental and dominant ingredient remains bitumen.