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: Skin
Sawtooth rete ridges are seen in: 
Select and explain. 
A. Erythroderma, B. Psoriasis, C. Dariers disease, D. Lichen planus
D: Lichen planus
Answer: D: Lichen planus 
Explanation: Ans. d. Lichen planusHPE of Lichen PlanusHyperkeratosisHypergranulosisAcanthosisBasal cell degeneration producing Civatte bodiesMax-Joseph SpaceBand like infiltration of Lymphocytes at dermo- epidermal junction.Saw toothing of Rete - Ridges