Answer: A) heat
B) pressure
C) deposition
D) Chemical environment
Step-by-step explanation:
Metamorphic rocks are the rocks which are formed by the pre-existing igneous and sedimentary rocks. These rocks are formed under the earth crust . During the formation of the rock the parent rock undergoes with physical, and chemical changes caused by the heat, pressure, addition or deposition of minerals from underground water and by the weathering process. The chemical composition of the rocks may vary due to the environment like a marine environment will administer salts into the rocks.