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
All of the following are signs of internal malignancy except – 
Select and explain. 
A. Acanthosis nigricans & annular erythema, B. Bullous pyoderma & migratory necrotizing erythema, C. Granuloma annulare, D. Erythema annulare
C: Granuloma annulare
Answer: C: Granuloma annulare 
Explanation: None