Which step is part of the formation of a batholith? heat and pressure change a pluton into metamorphic rock. a single pluton enlarges into a huge mass by melting the rock around it. lava flows across a mountain or plain, and then hardens into rock. many plutons clump together as they rise through the crust.

The step that is part in the formation of the batholiths is a single pluton enlarges into a huge mass by melting the rock around it. A single pluton does not enlarge into a huge mass, instead, it will melt due to the buoyant magma that surrounds it.

the answer to your question is:

c. complementary base-pairing