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: Radiology
[{'content': 'Joint mice are seen in the following disease : \nSelect and explain. \nA. Osteoarthritis, B. Rheumatoid arthritis, C. Juvenile arthritis, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Degenerative joint disease or osteoarthritis is a non-inflammatory disorder of joints characterized by joint deterioration and new bone formation. The new bone formed is called osteophyte. In severe cases, the osteophytes may break-off and lie free within joint space. These fragments are known as "Joint mice or mouse" and these must be differentiated from other conditions that cause joint radiopacities.', 'role': 'assistant'}]