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
Space maintainers are usually needed in the: 
Select and explain. 
A. Mandibular primary incisor teeth area, B. Mandibular primary canine teeth area, C. Mandibular primary second molar area, D. Maxillary primary incisor teeth area
C: Mandibular primary second molar area
Answer: C: Mandibular primary second molar area 
Explanation: None