<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:During a clinical study evaluating the effects of exercise on muscle perfusion, 15 healthy individuals perform a 20-minute treadmill run at submaximal effort. Before and after the treadmill session, perfusion of the quadriceps muscle is evaluated with contrast-enhanced magnetic resonance imaging. The study shows a significant increase in muscle blood flow per unit of tissue mass. Which of the following local changes is most likely involved in the observed change in perfusion?? A: Increase in thromboxane A2, B: Decrease in prostacyclin, C: Increase in endothelin, D: Increase in adenosine, E: Decrease in potassiumn,  <response>: This is a question about the physiological changes that occur during exercise that lead to increased muscle perfusion. The key details in the question stem are that there is increased perfusion of the quadriceps muscle during exercise. Of the choices given, an increase in adenosine choice D is the most likely local change that would cause increased muscle perfusion during exercise. Adenosine is a vasodilator that is produced in tissues like muscle when oxygen demand increases, as occurs during exercise. Vasodilation increases blood flow to the muscle.Choices A, B, and C are changes that would decrease, not increase perfusion. Thromboxane A2 and endothelin are vasoconstrictors, while prostacyclin is a vasodilator. Choice E, a decrease in potassium, may occur with exercise but is not directly related to the increased perfusion.D: Increase in adenosine 