Which type of rock is formed under extreme pressure over time?

Metamorphic rock is formed under extreme pressure and temperature conditions over long periods of time. This process, known as metamorphism, transforms existing rocks—either igneous, sedimentary, or other metamorphic rocks—into a new type of rock with different mineralogical and textural characteristics. The intense pressure can cause mineral grains to realign, grow, or recrystallize, resulting in a denser and more compact structure compared to the original rock.

Igneous rocks are the result of the cooling and solidification of molten material (magma or lava) rather than the result of pressure. Sedimentary rocks are formed from the accumulation and cementation of mineral and organic particles, usually in a more laid-back process involving sediments rather than the intense conditions required for metamorphic processes. The term "cemented rock" is not a formal classification in geology but refers to the process related to sedimentary rocks. Thus, metamorphic rock is the correct type that indicates formation through extreme pressure over time.