This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Papulosquamous disorders, Subject name: Dental
This is seen commonly in 
Select and explain. 
A. SLE, B. Lichen planus, C. Psoriasis, D. Leprosy
B: Lichen planus
Answer: B: Lichen planus 
Explanation: Surface of the papules in lichen planus often reveals a network of grey lines (Wickham's striae). Typically seen in oral mucosa Oral lichen planus (LIE-kun PLAY-nus) is an ongoing (chronic) inflammatory condition that affects mucous membranes inside your mouth. Oral lichen planus may appear as white, lacy patches; red, swollen tissues; or open sores. These lesions may cause burning, pain or other discomfo. Ref: Harrison 19e pg: 349