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': 'Which of the following is weakest antigen \nSelect and explain. \nA. Nucleic acids, B. Proteins, C. Carbohydrates, D. Lipids', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Proteins are stronger immunogens followed by carbohydrates, Lipids, Nucleic acids.', 'role': 'assistant'}]