<span>All the options (heat, pressure, deposition and chemical environment) are correct.<span> Metamorphic rocks are formed when pre-existing rocks are subjected to heat, pressure and hot mineral rich fluids which cause physical, chemical and mineralogical changes to the rock. Metamorphic rocks are grouped by chemical, texture and mineralogy. The common metamorphic rocks include schist, marble, and gneiss. </span></span>
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.
