The two organ systems that work together to regulate most aspects of the body's water balance are

Correct Answer: D

Rationale: The urinary system regulates water excretion, and the cardiovascular system maintains blood volume and pressure, together controlling water balance.

Correct Answer: D

Rationale: Osmoreceptors in the hypothalamus detect changes in plasma osmolarity and trigger responses like vasopressin release.

Correct Answer: C

Rationale: Active sodium reabsorption creates an osmotic gradient that drives passive water reabsorption.

Correct Answer: B

Rationale: Angiotensin II activates sympathetic, not parasympathetic, output to raise blood pressure.

Correct Answer: B

Rationale: The kidneys are the primary organ for excreting excess potassium via urine.