This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Which of the following is most Likely to be fatal? 
Select and explain. 
A. Osteochondroma, B. Giant cell tumour, C. Paget's disease, D. Multiple myeloma
D: Multiple myeloma
Answer: D: Multiple myeloma 
Explanation: None