This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardio thoracic surgery  , Subject name: Surgery
In patients who present with a penetrating chest injury, injury to the hea is most likely when the following physical sign is present 
Select and explain. 
A. Hypotension, B. Distended neck veins, C. Decreased hea sound, D. Decreased venous pressure
D: Decreased venous pressure
Answer: D: Decreased venous pressure 
Explanation: Hypotension increased venous pressure (distended neck veins), and decreased hea sounds make up the classic Beck's triad associated with cardiac tamponade. If these three findings are present in a person who has a penetrating chest wound, the intracardiac injury is almost ceain and operative intervention is mandatory.