Final answer:
Serpentinization is the process of altering certain rock types into serpentinite through hydration, which falls under the category of metamorphism and results in the formation of metamorphic rocks.
Step-by-step explanation:
Serpentinization is best defined as the alteration of certain rock types into serpentinite through hydration, making the correct answer (c) The alteration of certain rock types into serpentinite through hydration. This is a specific type of metamorphism, a geological process that transforms the composition and structure of rocks due to factors such as heat, pressure, and chemically reactive fluids. In the case of serpentinization, the process typically involves the addition of water into the rock's crystal structure, leading to the formation of new minerals, particularly within the group called serpentine. It is a crucial process in the rock cycle and plays a significant role in the formation of metamorphic rocks.
Unlike other rock-forming processes like the cementation process, which transforms clastic sediments into rocks by the precipitation of mineral matter in their pore spaces, or the formation of igneous rocks through magma solidification, serpentinization specifically refers to the transformation of ultramafic and mafic rocks, often peridotite and dunite, into serpentinite through the incorporation of water into their mineral structure.
The lithosphere, which consists of the Earth's crust and the uppermost mantle, is where these processes occur, and they can significantly change the physical and chemical characteristics of the rocks involved, reflecting the dynamic and ongoing nature of Earth's geology.