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': 'Molecular size of protein is determined by? \nSelect and explain. \nA. Sedimentation, B. SDS-PAGE, C. Salting out, D. Liophilization', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The molecular size of protein is estimated usually by SDS-PAGE. Other common methods are mass spectroscopy and MALDI.', 'role': 'assistant'}]