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
Hemorrhagic fever is caused by- 
Select and explain. 
A. West-Nile fever, B. Sandfly fever, C. Ebola virus, D. All of the above
C: Ebola virus
Answer: C: Ebola virus 
Explanation: None