The study of cells is called cell biology. There are two types on the basis of their number and these are unicellular and multicellular.
The correct answer to the question is option C which is the nucleolus.
According to the question, the correct answer is the nucleolus. The nucleolus is the darkly stained organelle present in the nucleus which stores all the DNA content of the mitochondria.
Hence, the correct answer is option C.
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https://brainly.com/question/12985618