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
7th Pandemic of cholera was caused by - 
Select and explain. 
A. El Tor, B. 0139 V. cholerae, C. Classical V. cholerae, D. V mimicus
A: El Tor
Answer: A: El Tor 
Explanation: Ans. is `a' i.e., El Tor