Answer: C) Functions as the powerhouse of the cell
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Explanation:
The mitochondria is responsible for generating the cell's energy, hence the phrasing "the mitochondria is the powerhouse of the cell".
The nucleus holds the DNA, so we can rule out choice B. The DNA in turn is connected to forming the proteins. The actual protein synthesis happens in the ribosomes, but the DNA is used as a blueprint (more or less) to assemble the correct amino acids in the correct order to form the complicated protein chains. In short, the nucleus indirectly helps direct the protein synthesis, so we can rule out choice A.
