Which of the following is/are used by bacteria for their reproduction?

The correct option is D All of the above
Bacteria reproduce mainly by fission in which a bacterial cell divides into two daughter bacterial cells. Under unfavourable conditions, they reproduce through spores ie., by the formation of endospores.
They also reproduce by sexual reproduction by adopting a primitive type of DNA transfer from one bacterium to the other by the process of transformation, conjugation or transduction.