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: Forensic Medicine
Provisional callus forms in fracture of bone by : 
Select and explain. 
A. 3 days, B. 7 days, C. 14 days, D. 30 days
B: 7 days
Answer: B: 7 days 
Explanation: B i.e. 7 days