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
Healing in root fracture occurs as the fracture line appears as thin radiolucent line, segment would be closely adapted, this healing is with: 
Select and explain. 
A. Calcified tissue., B. Connective tissue., C. Connective tissue+ calcified tissue., D. Granulation tissue.
A: Calcified tissue.
Answer: A: Calcified tissue. 
Explanation: None