Answer: "Option B- It pumps water out of the cell".
Explanation:
Vacuoles in the cell organism are responsible to maintain the amount of water in the cell body, to get stable in the environment vacuoles either remove or absorb the water through the mechanism of osmosis or osmoregulation.
Homeostasis is the phenomenon of maintaining balance of physical and chemical conditions of organism according to the environmental conditions to survive in it.
In single celled organisms, contractile vacuole pumps out the water from the cell through osmoregulation and excess of water is pumped out by the contractile vacuole.