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: Surgery
The most common site of lymphangiosarcoma is 
Select and explain. 
A. Liver, B. Spleen, C. Post mastectomy edema of arm, D. Retroperitoenum
C: Post mastectomy edema of arm
Answer: C: Post mastectomy edema of arm 
Explanation: Lymphangiosarcoma is a rare tumor that develops as a complication of long-standing (usually more than 10 years lymphedema.