Dr. Wagner is investigating a newly discovered, disease causing agent. She
determines that one structure in the agent is double-stranded RNA. What kind of
agent is Dr. Wagner studying?
A.virus
B. Protist
C. Fungus
D. Bacterium
Double-stranded RNA viruses (dsRNA viruses) are a polyphyletic group of viruses that have double-stranded genomes made of ribonucleic acid. ... The two groups do not share a common dsRNA virus ancestor. Double-stranded RNA viruses evolved two separate times from positive-strand RNA viruses. So therefore your answer is A
