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
Size of Nano filled composite is: 
Select and explain. 
A. 0.001-0.01 micron, B. 0.005-0.02 micron, C. Both 1 and 2, D. None of the above
C: Both 1 and 2
Answer: C: Both 1 and 2 
Explanation: None