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': 'Arecanut chewing is aetiological factor in \nSelect and explain. \nA. Leukoedema, B. Oral submucous fibrosis, C. Erythema multiforme, D. Oral lichen planus', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]