The following were the observations made for an infectious agent. (i) smaller than a virus, (ii) its nucleic acid had ribose as sugar (iii) lacks a protein coat. Select the disease/s it is most likely to cause.

Step-by-step solution

Potato spindle tuber disease affects the potato plant where the tubers are malformed and stunts the growth of the plant. This disease is caused by viroids which are smaller than virus and without any capsid covering of protein. It is basically a free floating single strand RNA.