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: Medicine
Swan Ganz. catheter is used for - 
Select and explain. 
A. Lt. cardiac output, B. Pulmonary capillary pressure, C. O2 saturation in mixed venous blood, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None