This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
Heparin acts 
Select and explain. 
A. Antithrombin III, B. Factor VIII, C. Thromboplastin, D. Factor V
A: Antithrombin III
Answer: A: Antithrombin III 
Explanation: .