This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General, Subject name: Anatomy
Which of the following bone ossifies in membrane 
Select and explain. 
A. Humerus, B. Clavicle, C. Femur, D. Radius
B: Clavicle
Answer: B: Clavicle 
Explanation: (Clavicle) (7-BDC-l 4th)Important features of clavicle1. It is the only long bone that lies horizontally2. It is subcutaneous throughout3. It is the first bone to start ossifying4. It is the only long bones which ossifies in membrane5. It is the only long bones which has two primary centres of ossification6. It is generally said to have no medullary cavity, but this is not always true7. It is occasionally pierced by the middle supraclavicular nerve.