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
Single layer of varnish covers: 
Select and explain. 
A. 55% of surface area, B. 25% of surface area, C. 35% of surface area, D. 80% of surface area
A: 55% of surface area
Answer: A: 55% of surface area 
Explanation: Single layer of varnish cover - 55% of surface area.
2-3 layers applied ⇒ 60 – 80% surface area covered.