Blood circulates from arteries to veins through microscopic vessels known as-

Correct option is C

The correct answer is (c) Capillaries.
· Capillaries are the smallest of a body's blood vessels that make up the microcirculation. Their endothelial linings are only one cell layer thick. Capillaries connect the arterial system with the venous system, serving as the exchange sites for nutrients, waste, oxygen, and carbon dioxide between blood and surrounding tissues.
· Blood flows from arteries to arterioles and then into the capillary networks where the exchange of gases and nutrients occurs. The blood then flows out of the capillaries into venules and subsequently into larger veins, completing the circuit back to the heart.
· The role of capillaries is crucial because they directly service the cellular needs of the body's tissues. They are pervasive throughout almost all tissues and are essential for maintaining cellular environments and homeostasis.
Additional details on other options:
· Corpuscles: This term generally refers to blood cells (red or white blood corpuscles) and is not related to the vessels through which blood flows.
· Cells: Cells are the basic building blocks of all living organisms.
· Calories: This is a unit of energy and has no relation to the structure or function of blood circulation systems.