Correct Option (b)
Reason : Bacterial strains such as of E. coli show sexual differences. Each male cell possesses a sex factor or fertility factor called F-factor. Infact, it is a small circular piece of DNA, self-replicating like bacterial chromosome but only 1/100 in size. The F-factor codes for the protein of a special type of pilus, the sex pilus which enables cell to cell contact and transfer of genetic material through a conjugation tube.
Correct Option (b) Reason : Bacterial strains such as of E. coli show sexual differences. Each male cell possesses a sex factor or fertility factor called F-factor. Infact, it is a small circular piece of DNA, self-replicating like bacterial chromosome but only 1/100 in size. The F-factor codes for the protein of a special type of pilus, the sex pilus which enables cell to cell contact and transfer of genetic material through a conjugation tube.