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: Unknown
The most important factor that influences the outcome of penetrating cardiac injuries is: 
Select and explain. 
A. Comminuted tear of a single chamber., B. Multiple-chamber injuries, C. Coronary artery injury., D. Tangential injuries.
C: Coronary artery injury.
Answer: C: Coronary artery injury. 
Explanation: Multiple studies in the literature confirm that injuries to the coronary arteries are the most important factor in determining outcome after a penetrating cardiac injury. Tangential injuries are the least serious. Injury to a single chamber—even if comminuted—or to multiple chambers is less likely to be fatal than are injuries that involve a major coronary artery.