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': 'All of the following belong to the group of microbial sensors, EXCEPT: \nSelect and explain. \nA. TLRs, B. NOD-like receptors (NLRs), C. MDA-5, D. None of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: When a pathogen enters the skin, it is confronted with macrophages and other phagocytic cells possessing "microbial sensors." There are three major groups of microbial sensors: (1) TLRs, (2) NOD-like receptors (NLRs), and (3) RIG-1 like helicases and MDA-5. Ref: Brooks G.F. (2013). Chapter 8. Immunology. In G.F. Brooks (Ed), Jawetz, Melnick, & Adelberg\'s Medical Microbiology, 26e.', 'role': 'assistant'}]