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 organisms shows bipolar staining except ? \nSelect and explain. \nA. Calymmatobacter granulomati, B. Y. pestis, C. Pseudomonas mallei, D. H. influenzae', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e., H. influenzae Safety pin appearance (Bipolar staining) yersinia pestis Vibrio parahemolyticus Burkholderia mallei Burkholderia pseduomallei Klebsiella granulomatis", 'role': 'assistant'}]