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': "Salt pepper appearance is seen in intraorat periapical radiograph of: \nSelect and explain. \nA. Thalassemia, B. Sjogren's syndrome, C. Periodontal abscess, D. Osteoporosis", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]