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
[{'content': 'You have to draw blood from a patient. When will you\ngive EDTA? \nSelect and explain. \nA. Orally starting several days before, B. Through I.V. route before drawing blood, C. EDTA is not an anticoagulant, D. EDTA will be added in test tube', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]