Which of the Following Is NOT an Example of Viral $\sigma$

Which of the following is NOT an example of viral gene product used to avoid the antiviral effects of the PKR enzymes?

A) Adenovirus VA I RNAs
B) Vaccinia SK-1 protein
C) Reovirus $\sigma$ 3 capsid protein
D) HIV tat transactivator
E) These are all examples of anti-PKR proteins.