Information on Rhabdovirus genome :
Viruses are classified by their genome. They can contain DNA or RNA. They can have a single or double strand of RNA or DNA.
The aim of this question is not to see whether candidates have memorised the genome of rhabdovirus. The description tells us that the virus contains a single strand of RNA initially, thus the first, second and last answer options cannot be correct.
If the strand of RNA was used directly as mRNA it would be positive-sense RNA. Examples include: picornavirus, flavivirus, coronavirus, and calicivirus.
We are told however that the strand needs to be copied by RNA polymerase to generate a complementary strand of RNA which then acts as mRNA. This is the definition of negative-sense RNA.
Viral infections in paediatric patients receiving conventional cancer chemotherapy — Simon et al. 93 (10): 880 — Archives of Disease in Childhood
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The severe acute respiratory syndrome coronavirus in tears — Tong and Lai 89 (3): 392 — British Journal of Ophthalmology