Answer: D) precapillary sphincters relax.
Explanation:
Blood flow to a tissue will decrease if precapillary sphincters relax as, capillaries provides glucose and oxygen to the cells and allows blood to flow through it when the muscle ring known as the precapillary Sphincters get relaxed. The blood flow is stopped when the precapillary sphincters constrict flow of blood. As, certain chemical signals causes feeder arterioles to dilate and bring more blood into local areas then, it causes precapillary sphincters to relax.
