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
Average thickness of the periodontal ligament is 
Select and explain. 
A. 0.15 to 0.38 mm, B. 0.05-015 mm, C. 0.38 -0.48 mm, D. 0.26-0.38 mm
A: 0.15 to 0.38 mm
Answer: A: 0.15 to 0.38 mm 
Explanation: None