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
A 4-year-old child has a normal complement of primary teeth, but they are grey and exhibit extensive occlusal and incisal wear. Radiographic examination indicates extensive deposits of secondary dentin in these teeth. Most likely this condition is: 
Select and explain. 
A. Neonatal hypoplasia, B. Amelogenesis imperfecta, C. Cleidocranial dysplasia, D. Dentinogenesis imperfecta
D: Dentinogenesis imperfecta
Answer: D: Dentinogenesis imperfecta 
Explanation: None