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
What is the most common cause of osteoblastic bone metastasis in females? 
Select and explain. 
A. Ca breast, B. Ca cervix, C. Ca thyroid, D. Osteosarcoma
A: Ca breast
Answer: A: Ca breast 
Explanation: 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.