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: Radiology
Soft tissue mass in the chest with rib erosion in X-ray is seen in all except - 
Select and explain. 
A. Leukemia, B. Ewing's sarcoma, C. Multiple myeloma, D. Osteosarcoma
A: Leukemia
Answer: A: Leukemia 
Explanation: Multiple myeloma, Ewing's sarcoma and parosteal osteosarcoma can cause rib lesion with adjacent soft tissue mass.
Leukemia does not cause rib lesion with adjacent soft tissue mass.