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
[{'content': 'Which is the best parameter to monitor LMWH? \nSelect and explain. \nA. aPTT, B. PT, C. INR, D. An Xa level', 'role': 'user'}, {'content': 'Answer: D \nExplanation: LMWH does not need any monitoring except in some special circumstances like pregnancy and old age and kidney disease. And Xa level is best parameter for its monitoring.', 'role': 'assistant'}]