Metamorphic rock can be formed from sedimentary rocks by the activity of heat and pressure.

Here's how it works:

* Heat: Intense heat from the Earth's interior or from nearby magma can cause the minerals in sedimentary rocks to recrystallize and change their structure.

* Pressure: The immense pressure from overlying rock layers or tectonic forces can also cause changes in the mineral composition and texture of sedimentary rocks.

This combination of heat and pressure is what transforms sedimentary rocks into metamorphic rocks.