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: Pathology
Median rhomboid glossitis is due to: 
Select and explain. 
A. Inflammation of the tongue, B. Persistence of tuberculum impar, C. Hypertrophy of filiform papillae, D. Atrophy of filiform papillae
B: Persistence of tuberculum impar
Answer: B: Persistence of tuberculum impar 
Explanation: None