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
Bass brushing technique: 
Select and explain. 
A. Cleans teeth from gingival margins, B. Stimulates gingiva, C. Interdentat spaces, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None