This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lichen planus and Other papulosquamous disorders, Subject name: Dental
A child came with similar lesions over elbows, shaft of penis and forearm. shows pinhead discrete but grouped papules over right elbow. Diagnosis? 
Select and explain. 
A. Lichen nitidus, B. Lichen planus, C. Scabies, D. Phrynoderma
A: Lichen nitidus
Answer: A: Lichen nitidus 
Explanation: Lichen nitidus : Grouped pin head sized papules on- Elbow- Forearm- Dorsum of hand- Shaft of penis Histology shows :Elongated rete ridgesLymphocytic infiltrateTogether they give " claw clutching appearance" Phrynoderma: keratotic papules with intrafollicular plugging on extensor surfaces.