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
Base metal alloys are useful for 
Select and explain. 
A. Cast partial dentures, B. Crowns, C. Orthodontic wires, D. all of the above
D: all of the above
Answer: D: all of the above 
Explanation: None