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: Microbiology
[{'content': 'Variable portion of antibody molecule is - \nSelect and explain. \nA. C-Terminal, B. N-Terminal, C. CHO moiety, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]