This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ohopedics Oncology, Subject name: Orthopaedics
Most common site of Osteogenic sarcoma is: 
Select and explain. 
A. Femur, upper end, B. Femur, lower end, C. Tibia, upper, D. Tibia, lower end
B: Femur, lower end
Answer: B: Femur, lower end 
Explanation: Osteosarcoma and GCT involves lower end of femur commonly