This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy and physiology of bone and fracture healing, Subject name: Orthopaedics
Initial stage of clinical union of bone is equivalent to 
Select and explain. 
A. Callus formation with woven bone, B. Woven bone Formation, C. Haematoma formation, D. Calcification formation only
A: Callus formation with woven bone
Answer: A: Callus formation with woven bone 
Explanation: The first signs of union are seen in stage of hard callus formation A. Clinical sign:fracture is no more mobile B. Radilogical sign :callus is seen on X ray *hard callus is immature woven bone* Ref: Maheshwari 9th/e p 12