Viruses are non-cellular organisms, but replicate themselves once they infect the host cell. To which of the following kingdom do viruses belong to?
1.  Monera

2.  Protista

3.  Fungi

4. -None of these

(d) In five kingdom classification of Whittaker, non-cellular organisms like viruses and viroids are not mentioned. Viruses did not find a place in classification since they are not truly ‘living’ and hence, they are considered as non-cellular.
Monera includes all unicellular prokaryotes called bacteria in which viruses can not be
Protista includes all eukaryotic unicellular plant and animals and fungi are
heterotrophic /parasitic, cellular organism devoid of chlorophyll.