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: Surgery
[{'content': 'In Forrest classification visible clot at ulcer base is \nSelect and explain. \nA. 1A, B. 2A, C. 2B, D. 3', 'role': 'user'}, {'content': 'Answer: C \nExplanation: FORREST - Classification of upper gastrointestinal hemorrhage\nAcute hemorrhage\nForrest IA - Active spurting hemorrhage\nForrest IB - Oozing hemorrhage\nSigns of recent hemorrhage\nForrest IIA - Non-bleeding visible vessel\nForrest IIB - Adherent clot\nForrest IIC - Hematin on ulcer base\nLesions without active bleeding\nForrest III - Clean-base ulcers.', 'role': 'assistant'}]