Final answer:
Metamorphic rocks do not require exposure to sunlight for cementation. Metamorphism occurs due to changes in temperature and pressure, either caused by deep burial or tectonic forces. The exposure of metamorphic rocks at the Earth's surface is typically a result of erosion.
Step-by-step explanation:
Metamorphic rocks do not require exposure to sunlight for cementation. Metamorphism occurs due to changes in temperature and pressure, either caused by deep burial or tectonic forces. When rocks undergo metamorphism, existing minerals may recrystallize or new minerals may form, resulting in a different rock composition and texture. The exposure of metamorphic rocks at the Earth's surface is typically a result of erosion, where overlying rocks are removed to reveal the deeper, high-grade metamorphic rocks.