the cell membrane A. is a rigid ,solid barrier around the cell. B..is made up mostly of lipids and nucleic acids. C... controls what enters and leaves the cell. or D... acts as a wall and dose not allow molecules to move across it.​

I'm fairly certain your answer is: C. (The cell membrane controls what enters and leaves the cell.)

Explanation:

In the definition of a cell membrane it says that its function is to protect the integrity of the interior of the cell by allowing certain substances into the cell while keeping other substances out. With this definition in mind, C would make the most sense.

Have a great day/night! ^^

both anaerobic and aerobic respiration use glucose (or other carbohydrates), proteins and lipids to produce atp and nadh. cell uses those energy molecules, obtained from food and   breaks them down during the chemical reactions of respiration. in anaerobic respiration, nadh is regenerated to nad+ by enzymes lactate dehydrogenase (lactate is produced, e.g. in muscle cells) or by alcohol dehydrogenase where ethanol is produced (alcohol fermentation), while in aerobic respiration, electrons from nadh are deposited in the mitochondria to regenerate nad+ (electron transport chain. anaerobic respiration produces 2 atp per molecule of glucose compared to aerobic respiration where about 38 atp molecules are produced.

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.