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
Features of multiple myeloma are 
Select and explain. 
A. B cell monoclonal proliferation, B. B cell in bone marrow, C. B cell in peripheral blood, D. Plasma cell secretes immunoglobulin
A: B cell monoclonal proliferation
Answer: A: B cell monoclonal proliferation 
Explanation: Multiple myeloma is a malignant proliferation of plasma cells. Normal plasma cells are derived from B cells & prodece immunoglobulins which contain heavy & light chains. Normal immunoglobulins are polyclonal,which means that a variety of heavy chains are produced . In myelona,plasma cells produce immunoglobulin of a single hwavy & light chain , a monoclonal protein commonly referred to as a paraprotein.Reference :Davidson's principles &practice of medicine 22nd edition pg no 1046.