This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oncology, Subject name: Surgery
In which case spontaneous regression is not seen? 
Select and explain. 
A. Malignant melanoma, B. Osteosarcoma, C. Neuroblastoma, D. Choriocarcinoma
B: Osteosarcoma
Answer: B: Osteosarcoma 
Explanation: Tumors with spontaneous regression Neuroblastoma Choriocarcinoma Renal cell carcinoma Malignant melanoma Retinoblastoma