This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Compensating mechanisms involved at high altitude is 
Select and explain. 
A. Hyperventilation, B. Hypoventilation, C. Respiratory depression, D. Respiratory acidosis
A: Hyperventilation
Answer: A: Hyperventilation 
Explanation: The most important compensatory mechanism that occurs at high altitude is hyperventilation. This may lead to respiratory alkalosis which is not a compensatory effect but may cause an opposing effect at the respiratory centre, to hypoxic stimulation.