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: Pathology
[{'content': 'A most characteristic feature of acute in \nSelect and explain. \nA. Vasoconstriction, B. Vascular stasis, C. Margination of leucocytes, D. Vasodilatation and increased vascular permeability', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Acute inflammation\xa0has three major steps: -\nAmong these three major steps “The hallmark of acute inflammation\xa0is increased vascular permeability leading to\xa0escape of protein-rich fluid\xa0(exudates) into the extravascular tissue”.\nMechanism of increased vascular permeability\ni. Formation of endothelial gaps in venules\nii. Direct endothelial injury resulting in endothelial cell necrosis and detachment.\niii. Delayed prolonged leakage\niv. Leucocyte mediated endothelial injury.', 'role': 'assistant'}]