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: Surgery
Tension pneumothorax results in 
Select and explain. 
A. Alkalosis, B. Increased cardiac output, C. Decreased venous return, D. All of the above
C: Decreased venous return
Answer: C: Decreased venous return 
Explanation: None