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 type of GIC is used as a base? 
Select and explain. 
A. Type I, B. Type IIa, C. Type IIb, D. Type III
D: Type III
Answer: D: Type III 
Explanation: Type I: Luting crowns, bridges and orthodontic brackets.
Type IIa: Esthetic restorative cements.
Type IIb: Reinforced restorative cements.
Type III: Lining cements, base.
Ref: Phillip’s Science of Dental Materials ed 12 pg 320