The melting of metamorphic or igneous rock forms what substance? How? Why?

Extreme pressure from burial, increasing temperature at depth, and a lot of time, can alter any rock type to form a metamorphic rock. If the newly formed metamorphic rock continues to heat, it can eventually melt and become molten (magma). When the molten rock cools it forms an igneous rock.

c. 75.7

i think that is the right