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
In which of the following conditions are the Aschoff bodies observed? 
Select and explain. 
A. Acute myelogenous leukemia, B. Pheochromocytoma, C. Osteopetrosis, D. Rheumatic fever
D: Rheumatic fever
Answer: D: Rheumatic fever 
Explanation: Aschoff bodies are the classic lesions observed in rheumatic fever. They are areas of focal necrosis surrounded by a dense inflammatory infiltration and may be observed in heart tissues.