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
Expansile lytic osseous metastases are characteristics of primary malignancy of - 
Select and explain. 
A. Kidney, B. Bronchus, C. Breast, D. Prostate
A: Kidney
Answer: A: Kidney 
Explanation: Renal (kidney) carcinoma       →       Osteolytic bone metastasis.
Breast and lung (bronchus)     →       Mixed osteolytic - Osteoblastic
Prostate carcinoma                →       Osteoblastic metastasis