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
The greatest advantage of using extra oral anchorage is that: 
Select and explain. 
A. More force can be applied, B. It has a direct reciprocal action on opposing arch, C. It permits posterior movement of teeth in one arch without disturbing the opposing arch adversely, D. Any of the above
C: It permits posterior movement of teeth in one arch without disturbing the opposing arch adversely
Answer: C: It permits posterior movement of teeth in one arch without disturbing the opposing arch adversely 
Explanation: None