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': 'All are true about heparin except : \nSelect and explain. \nA. Antidote is protamine sulfate, B. Can be administered only in vivo, C. Cannot be given orally, D. Increases APTT', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]