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
Category A bioterrorism agents are-a) Ebolab) Yersiniac) Clostridium botulinumd) Rickettsiae) Cholera 
Select and explain. 
A. abc, B. bcd, C. abe, D. acd
A: abc
Answer: A: abc 
Explanation: None