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
Predisposing factors for skin ca are – a) Lichen planusb) Bowen's diseasec) Psoriasisd) Bechet's diseasee) UV rays 
Select and explain. 
A. abc, B. bcd, C. abe, D. acd
C: abe
Answer: C: abe 
Explanation: Hypertrophic lichen planus and Bowen's disease are premalignant conditions of SCC of skin.
UV rays is the most important predisposing factor for SCC of skin.