Answer: 3. C. mitochondrion
Step-by-step explanation:
Mitochondrion in a cell is defined as the powerhouse of the cell which provide energy to the whole cell.
A mitochondrion is has a membranous layer and bean-shaped organelle that is the “energy transformer” of the cell. They contibute to the biochemical processes of the cell called cellular respiration. They works as a digestive system which takes nutrients, breaks them into several energy rich molecules for the cell.
Hence, the correct answer is 3. C. "mitochondrion".