Viroids are identified on the basis of which of the following three characteristic features?
(a) Much smaller in size than viruses
(b) Consist of circular RNA molecule
(c) RNA molecule covered by protein coat
(d) Infect the plant cells
1
(a), (b), (d)
2
(a), (b), (c)
3
(a), (c), (d)
4
(b), (c), (d)