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: Medicine
Leucocyte common antigen is seen in? 
Select and explain. 
A. Lymphoma, B. Ewing sarcoma, C. Rhabdomyosarcoma, D. Osteosarcoma
A: Lymphoma
Answer: A: Lymphoma 
Explanation: None