This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S., Subject name: Radiology
[{'content': 'Classification systems for Aortic dissection are? \nSelect and explain. \nA. Crawford, B. DeBakey, C. Stanford, D. All of above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D. All of aboveCLASSIFICATION SYSTEMS FOR AORTIC DISSECTION Classification systemSite of dissectionCrawfordDeBakeyStanfordBoth ascending and descending aortaProximal dissectionsType 1Type AAscending aorta and arch onlyProximal dissectionsType IIType ADescending aorta only (distal to left subclavian artery)Distal dissectionsType III IIIa--limited to thoracic aortaType B IIIb--extends to abdominal aorta In addition to the above, all dissections are classified as acute if the duration of symptoms is shorter than 14d and chronic if longer than this.', 'role': 'assistant'}]