This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumors, Subject name: Ophthalmology
[{'content': 'Most common site of bony metastases in Retinoblastoma- \nSelect and explain. \nA. Skull bones, B. Hip bones, C. Ribs, D. Veebrae', 'role': 'user'}, {'content': 'Answer: A \nExplanation: *Metastasis by blood stream occurs to skill bone and distal bones. Ref: AAO- Ophthalmic pathology and Intraocular Tumors, section 4, 2014-15 p.304.', 'role': 'assistant'}]