This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Photosensitive Disorders, Subject name: Skin
Which of the following produces pre-malignant lesions - 
Select and explain. 
A. Psoriasis, B. Erythema multiforme, C. Lichen planus, D. All of the above
C: Lichen planus
Answer: C: Lichen planus 
Explanation: Ans is 'c' i.e. Lichen planus "Oral LP, particularly the erosive (ulcerative variant) is prone to develop SCC, the frequency being 0.8%. Long standing disease and concurrent use of tobacco are the risk factors for malignant transformation. Tongue is the most common site for malignancy, followed by buccal mucosa." - IADVL text book of dermatology 3rd/e p. 1074