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: Microbiology
Most important element in treatment of diphtheria - 
Select and explain. 
A. Antitoxin, B. Tetracycline, C. Erythromycin, D. Penicillin
A: Antitoxin
Answer: A: Antitoxin 
Explanation: None