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: Unknown
Predominant osteoblastic secondaries are seen in - (Repeat) 
Select and explain. 
A. Prostate Ca, B. Breast Ca, C. Bone Ca, D. Stomach Ca
A: Prostate Ca
Answer: A: Prostate Ca 
Explanation: Ans: A (Prostate Ca) Ref: Robbins Pathologic Basis of Disease, 8th edition. Bone misc tumors chapter Pg. 1205Explanation:The radiographic manifestations of metastases purely lytic- purely blast it. or mixed lytic and blasticIn lytic lesions, the metastatic cells secrete substances such as prostaglandins, cytokines, and PTH-related protein that stimulate osteoclastic bone resorption; the tumor cells themselves do not directly resorb bone.Lysis of bone tissue rich in growth factors such as TGF-b, IGF-1, FGF. PDGF. and bone morphogenetic proteins, in turn, helps create an environment conducive to tumor cell growth.Prostate adenocarcinoma secretes WNT proteins that stimulate osteoblastic bone formation.Most metastases induce a mixed lytic and blastic reaction.Primaries which produce predominantly lytic bone lesionsCarcinoma of the kidneyCarcinoma of the lungCarcinoma of the gastrointestinal tractMalignant melanomaPrimaries which produce predominantlySclerotic/Osteoblastic lesionsProstate adenocarcinomaCa ColonCa Breast