This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Medicine
In lymphoplasmacytoid lymphoma which of the following monoclonal immunoglobulin is seen ? 
Select and explain. 
A. IgA, B. IgD, C. IgG, D. IgM
D: IgM
Answer: D: IgM 
Explanation: Waldenstrom macroglobulinaemia is a low grade lymphoplasmacytoid lymphoma associated with an Ig M paraprotein causing clinical features of hyperviscosity syndrome.Reference:Davidson's principles & practice of medicine 22nd edition pg no 1045