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
Mantle cell lymphomas are positive for all of the following except- 
Select and explain. 
A. CD23, B. CD20, C. CD5, D. Cyclin D1
A: CD23
Answer: A: CD23 
Explanation: Ans. is 'a' i.e., CD-23