This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Microbiology
[{'content': 'What is the most common cause of osteoblastic bone metastasis in females? \nSelect and explain. \nA. Ca breast, B. Ca cervix, C. Ca thyroid, D. Osteosarcoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The commonest cause of osteoblastic metastasis in women: Ca breastThe commonest in men is Ca prostateBone metastasis in Ca breast is of mixed type, i.e. both osteolytic & osteoblasticBut is predominantly osteolytic.Bone Metastasis :The most common site for secondaries is BoneSkeletal metastasis may be osteolytic or osteoblasticMost of the metastasis are mixed type; predominantly osteolytic.', 'role': 'assistant'}]