Bacteria involve  (exchange of DNA/fusion of gametes) during the sexual reproduction.

Find out the correct combination based on the methods of genetic material exchange which occur in bacteria.

Plasmids have the following characters.

i) They contain fewer genes than the bacterial chromosome.

ii) They have single stranded DNA

iii) They can be used as vectors

iv) They contain linear form of DNA

v) Plasmids confer protection to drugs

The correct combination is

Statement $\left(\mathrm{S}\right):$ In ciliates, conjugation restores the vigour and vitality which are lost due to chromosomal imbalance in the macronuclei due to repeated amitotic divisions.

Reason $\left(\mathrm{R}\right):$ Conjugation is temporary union of senile ciliates belonging to same mating types. It often prevents exchange of nuclear material.