Which is true of a medium? A. A medium is another term for empty space. B. A medium is a material through which mechanical waves cannot travel.
C. A medium is material through which mechanical waves can travel.​

temp rises, and expansion

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods