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
[{'content': 'Age changes in periodontal ligament include which of the following? \nSelect and explain. \nA. Increased fibroplasia, B. Increased vascularity, C. Increased thickness, D. Decreased in number of cementicles', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]