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: Biochemistry
[{'content': 'In which of the following tissues , is glycogen incapable of contributing directly to blood glucose \nSelect and explain. \nA. Liver, B. Muscles, C. Both, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]