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
Nanofillers are in the range of: 
Select and explain. 
A. 10 - 100 microns, B. 0.1 - 1 microns, C. 0.01 - 0.1 microns, D. 0.001 - 0.01 microns
D: 0.001 - 0.01 microns
Answer: D: 0.001 - 0.01 microns 
Explanation: None