This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'Which of the following chemical nature makes a better antigen? \nSelect and explain. \nA. Lipids, B. Nucleic acids, C. Polysachharides, D. Proteins', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Antigens are usually peptides, polysaccharides or lipids. In general, molecules other than peptides (saccharides and lipids) qualify as antigens but not as immunogens since they cannot elicit an immune response on their own. Ref: Ananthanarayan & Panikers textbook of microbiology 9th edition pg:88', 'role': 'assistant'}]