Answer:
Option (C)
Explanation:
Slate is a metamorphic rock which is characterized by the presence of fine grains that forms foliated structure.
Schist is a high-grade metamorphic rock which commonly characterized by the presence of foliated minerals.
The above-given condition describes the grade of metamorphism, where a low-grade metamorphic rock changes into a high-grade metamorphic rock due to the increase in the temperature and the pressure condition.
Slate is a low-grade metamorphic rock that changes into another metamorphic rock named Phyllite and because of the further increase in the temperature-pressure condition, it changes into a higher grade metamorphic rock named schist.
Phyllite is a metamorphic rock that is mainly comprised of minerals such as quartz, mica, and some chlorite.
Thus, the correct answer is option (C).