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: Radiology
The most definitive method of diagnosing pulmonary embolism is: 
Select and explain. 
A. Pulmonary ateriography, B. Radioisotope perfusion pulmonary scintigraphy, C. EKG, D. Venography
A: Pulmonary ateriography
Answer: A: Pulmonary ateriography 
Explanation: Ans. Pulmonary ateriography