Which of the following rocks is not metamorphic

The rock that is not metamorphic is Shale. Metamorphic rocks are formed from pre-existing rocks that have undergone physical and chemical changes due to high pressure, heat, or both. The process of metamorphism can cause the minerals in the original rock to recrystallize and form new minerals, resulting in a change in texture and composition. Schist, quartzite, and slate are all examples of metamorphic rocks. Schist is formed from shale or mudstone that has undergone high pressure and heat, causing the minerals in the rock to recrystallize into thin, platy layers. Quartzite is formed from sandstone that has undergone a process of recrystallization, cementation, and metamorphism. Slate is formed from shale or mudstone that has undergone low-grade regional metamorphism. Shale, on the other hand, is a sedimentary rock that is formed from compacted mud or clay. It is not formed through the process of metamorphism and therefore cannot be classified as a metamorphic rock. Therefore, Shale is the rock that is not metamorphic.