Question

which process correctly describes how igneous rocks are formed?
compaction and cementation of sediment
cooling of molten lava or magma
heating and added pressure to existing rock
evaporation of seawater

Explanation:

Igneous rocks form from the cooling and solidification of molten lava (on the Earth's surface) or magma (beneath the surface). Compaction and cementation form sedimentary rocks, heating and added pressure form metamorphic rocks, and evaporation of seawater is related to salt - formation, not igneous rock formation.

Answer:

Cooling of molten lava or magma