A. The mitochondria because it is the power house of the cell.
<span>any of various sustained exercises, as jogging, rowing, swimming, or cycling, that stimulate and strengthen the heart and lungs, thereby improving the body's utilization of oxygen. 2.
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I think the correct answer from the choices listed above is option D. It is reproduction that is the name of the process <span>in which an organism makes a new organism. Reproduction is the production of an offspring either by sexual or asexual process. Hope this answers the question.</span>