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: Dental
A space maintainer is least indicated for premature loss of a: 
Select and explain. 
A. Primary maxillary first molar, B. Primary mandibular first molar, C. Primary mandibular central incisor, D. Primary maxillary central incisor
D: Primary maxillary central incisor
Answer: D: Primary maxillary central incisor 
Explanation: None