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': 'Adhesin is useful in- \nSelect and explain. \nA. Motility, B. Bacterial attachment, C. Toxigenicity, D. Bacterial division', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Bacterial adhesins \n\nSpecific adhesion to host tissue cells is an essential virulence factor of most bacterial pathogens.\xa0\nThe fundamental process that determines bacterial attachment to host tissue surfaces is mediated by microbial adhesins.\nMost fimbriae of gram-negative bacteria function as adhesins, but in many cases, it is a minor subunit protein at the tip of the fimbriae that is actual adhesin.\nIn grain-positive bacteria, a protein or polysaccharide surface layer serves as the specific adhesin.', 'role': 'assistant'}]