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
Heavy chain disease with kapppa light chains in urine - 
Select and explain. 
A. Mu chain disease, B. Seligman disease, C. Franklin disease, D. waldenstrom macroglobulinemia
A: Mu chain disease
Answer: A: Mu chain disease 
Explanation: Answer- A. Mu chain diseaseMu HCD: Mu chain with associated light chain.