A. they have shared matter.
Answer & Explanation:
Feedback is a form of regulation where the main product of one reaction, can also inhibit it. It can work in several ways, mainly there's a receptor that, somehow, measures the presence of a determined molecule, in this case, ATP. These receptors can also be involved in the metabolic process and when there's an excess of ATP, the enzymes are inhibited, maybe with an allosteric type of inhibition.
The answer is A. An organism living at the bottom of the ocean is used to a high pressure so they cannot study them as the lower pressure kills the organisms as they reach the surface.