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
Drug which reaches maximum concentration in gingival 
fluid is: 
Select and explain. 
A. Tetracycline, B. Penicillin, C. Erythromycin, D. Sulphonamide
A: Tetracycline
Answer: A: Tetracycline 
Explanation: None