Final answer:
The extrinsic control of arterioles and vascular resistance includes hormones, particularly epinephrine and norepinephrine, and the sympathetic nervous system, which constricts blood vessels through adrenergic receptors.
Step-by-step explanation:
Extrinsic control of the arterioles and vascular resistance includes hormones and the sympathetic nervous system. Endocrine regulation of the cardiovascular system includes the hormones epinephrine and norepinephrine, which are released from the adrenal medulla and interact with adrenergic receptors in the vessels, causing vasoconstriction and raising blood pressure. Additionally, the sympathetic nervous system plays a crucial role in controlling vascular resistance through the release of norepinephrine that binds to adrenergic receptors on blood vessels.
Therefore, the correct answer to the question is 'C. Hormones and the sympathetic nervous system.' This option correctly identifies the two primary extrinsic mechanisms that regulate arteriole constriction and dilation, thus affecting vascular resistance and blood flow.