This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Medicine
Increased rouleaux formation in the peripheral blood is a characteristic feature of - 
Select and explain. 
A. Multiple myeloma, B. Non-Hodgmin's lymphoma, C. Tuberculosis, D. Malaria
A: Multiple myeloma
Answer: A: Multiple myeloma 
Explanation: Rouleaux in a Peripheral Smear, Multiple Myeloma. Rouleaux are linear aggregates of red blood cells that form in the presence of increased plasma proteins. This phenomenon differs from agglutination, in which red blood cells form grape like clusters due to the presence of antibodies bound to their surfaces Ref Davidson 23rd edition pg 976