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
Which of the following can be used as best root end filling material? 
Select and explain. 
A. MTA, B. ZOE, C. Amalgam, D. Calcium hydroxide
A: MTA
Answer: A: MTA 
Explanation: Clinical Note 

Amalgam was once the most common root-end filling material, but it is not recommended presently due to corrosion and dimensional changes, unsightly amalgam tattoos, biocompatibility, and safety issues. 
MTA is the recommended root end filling material of choice. 
IRM and SuperEBA are other commonly recommended alternatives.

Reference: Grossman endodontics, 13th ed page no 479