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: Pharmacology
[{'content': 'Low molecular weight heparin mainly inhibits which factor: September 2009 \nSelect and explain. \nA. Factor Ilia, B. Factor VIIIa, C. Factor Xa, D. Factor XIIa', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C: Factor Xa', 'role': 'assistant'}]