facies are expected at the core of mountains formed at a continental-continental convergent plate boundary.

Granulite.

Explanation:

A granulite can be defined as a set of cluster of metamorphic rock formulated by the process of metamorphism. Under this process of metamorphism, a granulite is essentially fashioned with or without quartz. A granulite facies are composed under the experience of high pressure/high temperature, which can be found at the core of continental crust.

Near the core of continental crust, the biotite mineral breaks down when under the high-temperature and forms the granulite facies from the composition of orthopyroxene, feldspar, and water.

Therefore, the correct answer is granulite facies.