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 is a dye used for dentinal caries detection: 
Select and explain. 
A. Calcein, B. Zygo ZL-22., C. Fuschin., D. Acid red system.
D: Acid red system.
Answer: D: Acid red system. 
Explanation: Dyes used in caries detection are: 
Enamel caries 

Calcein
 Zygo ZL-22
Fuschin

Dentinal caries  

 Acid red system
α - Aminoacridine