An existing rock is buried and subjected to intense heat and pressure over a long period. Which kind of rock results?

1. The starting material here is rock that already exists, not fresh magma. 2. Igneous rock needs magma to reach the surface as lava and then solidify. 3. Sedimentary rock needs loose fragments to be deposited and compacted. 4. Neither of those describes an existing rock squeezed and heated in place. 5. Metamorphic rock is formed when any other rock type is subjected to intense heat and pressure over time. 6. Slate and marble are the examples given, and both begin life as some other rock. _Source: Siyavula Physical Sciences Grade 11 (Everything Science, CC BY 4.0), Chapter 14: The lithosphere_