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
Macrophages containing large quantities of undigested and partial digested bacteria in the intestine are seen in - 
Select and explain. 
A. Whipple's disease, B. Amyloidosis, C. Immunoproliferative small intestinal disease, D. Vibrio cholerae infection
A: Whipple's disease
Answer: A: Whipple's disease 
Explanation: The hallmark of Whipple’s disease is a small intestinal mucosa laden with distended macrophages in the lamia propria.
The macrophages contain periodic acid– Schiff (PAS) positive granules and small rod shaped bacilli)