The correct option is D All of the above
Virus, viroids and lichens are not found under Whittaker's Five Kingdom classification because of the following reasons:
i) Virus are non-cellular organisms that are characterised by having an inert crystalline structure outside the living cell.
ii) Viroids are free RNA that lacked the protein coat.
iii) Lichens are symbiotic associations i.e., mutually useful associations, between algae and fungi.