Which constituent of petroleum is used for road paving/surfacing?

Why it is used for roads: Its waterproofing, adhesive and flexible properties make it an ideal binder in asphalt mixtures; it binds aggregates and resists deformation under traffic and weather.

Typical application: Bitumen is mixed with crushed stone or gravel to form asphalt (bituminous concrete) used as the wearing course or surfacing layer on roads.

Why the other listed petroleum constituents are not used for paving: Paraffin wax: a light solid used in candles and polishes; melts at low temperatures and lacks binder properties needed for roads.

Naphthalene: an aromatic solid used as a fumigant and chemical intermediate; not suitable as a binder.

Petroleum coke: a solid carbon-rich product used as fuel or in industry; its form and properties do not suit road surfacing.

Summary: Use bitumen for road paving because it acts as the binding, waterproofing, and durable component of asphalt.