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
ElekS Gel test is used in:( 
Select and explain. 
A. Influenza, B. Diphtheria, C. Brucellosis, D. Cholera
B: Diphtheria
Answer: B: Diphtheria 
Explanation: Diphtheria