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
Remnants of the Hertwig's root sheath are found in 
Select and explain. 
A. Gingiva, B. Alveolar bone, C. Periodontal ligament, D. Cementum
C: Periodontal ligament
Answer: C: Periodontal ligament 
Explanation: None