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
A one year old child having leucocoria was detected to be having a unilateral, large retinoblastoma filling half the globe. Current therapy would involve- 
Select and explain. 
A. Enucleation, B. Chemotherapy followed by local dyes, C. Direct laser ablation using photodynamic cryotherapy, D. Scleral radiotherapy followed by chemotherapy
A: Enucleation
Answer: A: Enucleation 
Explanation: *Tumor involving less than half of the globe- Multimodal therapy (chemoreduction followed by local destruction). *Tumor involving half or more of the globe - Enucleation. Ref: Wills Eye hospital at las of Clinical ophthalmology p.269.