Final answer:
The urinary system regulates blood volume and pressure by adjusting water loss in urine, releasing hormones like EPO and renin, and modulating sympathetic stimulation. Collectively, all of these mechanisms support the regulation of blood pressure. The correct option is 4) adjusting sympathetic stimulation.
Step-by-step explanation:
The urinary system regulates blood volume and pressure by several mechanisms, including: adjusting the volume of water lost in the urine, releasing erythropoietin (EPO), releasing renin, and adjusting sympathetic stimulation. Overall, all of the above options contribute to this regulatory process.
The kidneys adjust the volume of water excreted, influencing blood volume and pressure. The release of EPO by the kidneys stimulates red blood cell production, which can indirectly affect blood volume and viscosity. Renin is secreted in response to decreased blood pressure, activating the renin-angiotensin-aldosterone system, leading to sodium and water retention, thus increasing blood volume and pressure. Additionally, the urinary system interacts with the sympathetic nervous system to regulate blood vessel constriction and influence blood pressure.