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: Dental
[{'content': "Predisposing factors for skin ca are – a) Lichen planusb) Bowen's diseasec) Psoriasisd) Bechet's diseasee) UV rays \nSelect and explain. \nA. abc, B. bcd, C. abe, D. acd", 'role': 'user'}, {'content': "Answer: C \nExplanation: Hypertrophic lichen planus and Bowen's disease are premalignant conditions of SCC of skin.\nUV rays is the most important predisposing factor for SCC of skin.", 'role': 'assistant'}]