This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Surgery
Compensatory mechanisms during acute hemorrhage include 
Select and explain. 
A. Decreased cerebral and coronary blood flow, B. Decreased myocardial contractility, C. Renal and splanchnic vasodilation, D. Increased respiratory rate
D: Increased respiratory rate
Answer: D: Increased respiratory rate 
Explanation: Acute hemorrhage triggers the potent vasopressor activity of both angiotensin and vasopressin to increase blood flow to the heart and brain via selective vasoconstriction of the skin, kidneys, and splanchnic organs. Adrenergic discharge also results in selective vasoconstriction of skin, renal, and splanchnic vessels. Myocardial contractility and heart rate are increased, with a resultant increased cardiac output. Hyperventilation is the typical response to the metabolic (lactic) acidosis associated with hemorrhagic shock and hypoperfusion. Aldosterone release, with subsequent increased renal sodium resorption, is mediated by angiotensin II and ACTH, which prevents further intravascular depletion.