Why are viroids resistant to nucleases?
A.Having a circular RNA 'genome,' they are resistant to the digestion of most exonucleases (that nibble/digest the free ends of RNA or DNA).
B.Having a circular RNA 'genome,' with no protein shell, they are resistant to the protein-degrading activities of nucleases.
C.Nucleases will only digest DNA, not RNA-so viroids are protected.
D.Viroids have only been identified in plants.Plant nucleases cannot digest RNA.