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': 'An Immunoglobulin molecule represents the following level of organized protein structure \nSelect and explain. \nA. Primary structure, B. Secondary structure, C. Tertiary structure, D. Quartenary structure', 'role': 'user'}, {'content': 'Answer: D \nExplanation: A complete immunoglobulin molecule represents Ouanternary level of organization between four polypeptide chains (two light chains and two heavy chains). It has a heterotetrameric quaternary structure.', 'role': 'assistant'}]