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: Orthopaedics
A patient developed paraplegia. On routine examination and X-ray it was found that there are osteoblastic lesion in his spine. Most probable diagnosis is - 
Select and explain. 
A. Carcinoma thyroid, B. Ca. Prostate, C. Breast Ca., D. Pancreatic Ca.
B: Ca. Prostate
Answer: B: Ca. Prostate 
Explanation: Most common tumor producing osteoblastic bone metastasis is carcinoma prostate.