It is B, since it is at the end of the investigation
By controlling what enters and leaves a cell, the cell membrane A) aids in maintaining homeostasis within the cell. Homeostasis is the process by which organisms maintain life through eating, growing, and living in variable conditions. It would not make sense to answer B) because organisms do not control the homeostasis of their external environment. D) also would not be correct because cell's do not control osmosis in the external environment. The membrane does not control osmosis because osmosis is generally a random process of molecular diffusion whereas the membrane acts in a conscious and controlled way.
When the predators of a certain prey are removed, the prey is then allowed to populate and grow (unless a new predator emerges). In the case of the mice, if the rattlesnakes and foxes are removed, the number of mice will increase. Mice are able to reproduce easily and without the threat of elimination by their known predators, their population will likely increase dramatically.
ANSWER: The mice population will increase without known predator presence.
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