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
Patient complaining of retrosternal chest pain for more than half an hour is most likely to be: 
Select and explain. 
A. Angina, B. MI, C. CHF, D. Congenital heart problem
B: MI
Answer: B: MI 
Explanation: None