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
Gates Glidden drill is used to: 
Select and explain. 
A. Remove the lingual shoulder, B. Enlarge the canal orifice, C. For the preparation of post space, D. Both 1 and 2
D: Both 1 and 2
Answer: D: Both 1 and 2 
Explanation: The Gates-Glidden drill is used to:

Remove the lingual shoulder during access preparation of the anterior teeth
Enlarge root canal orifices.

Textbook of Endodontics Nisha GARG 3rd ED