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': 'Leucine-Zipper complex is \nSelect and explain. \nA. DNA binding protein, B. Membrane attack complex, C. B cell epitomes, D. Receptor ligand protein', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]