Question

part a the only blood vessels whose walls permit exchange between the blood and the surrounding interstitial fluids are the capillaries. venules. arterioles. arterioles and capillaries. venules and capillaries.

Explanation:

Capillaries have thin - walled structures that allow for the exchange of substances like oxygen, nutrients, and waste products between the blood and the interstitial fluid. Arteries, arterioles, venules, and veins have thicker walls or different functions that do not primarily focus on this type of exchange.

Answer:

capillaries