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
A 12-year-old boy had a gradually progressive plaque on a buttock for the last 3 years. The plaque was 15 cm in diameter, annular in shape, with crusting and induration at the periphery and scarring at the centre. The most likely diagnosis – 
Select and explain. 
A. Tinea corporis, B. Granuloma annulare, C. Lupus vulgaris, D. Borderline leprosy
C: Lupus vulgaris
Answer: C: Lupus vulgaris 
Explanation: This boy has


Annular plaque
On buttock
Crusting at periphery
Scarring at centre

These suggest the diagnosis of lupus vulgaris.
Annular lesions 

When the lesions of a skin disease are arranged in ring shape, they are called annular lesions.