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': 'Prokaryotes have all, except \nSelect and explain. \nA. Rigid cell wall, B. Flagella, C. Ribosomes, D. Well defined Nuclear membrane', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Prokaryotic cells have Cell wall, Cell membrane, ribosome, Nucleoid. BUT Nuclear membrane, nucleolus, endoplasmic reticulum, mitochondria are absent Ref: Ananthanarayana textbook of Microbiology 9th edition Pgno : 9', 'role': 'assistant'}]