The correct option is B A-RNA, B-RNA polymerase, C-Rho factor
The image given in the question represents the process of transcription in bacteria.
Transcription is the process of copying genetic information from one strand of the DNA (template strand) into RNA.
The DNA strand with polarity 3’ → 5’ acts as a template strand and the DNA strand with polarity 5’ → 3’ is called a coding strand.
The segment of DNA which gets transcribed has a transcription unit with a promoter, the structural gene and a terminator region.
The process of transcription in bacteria involves three steps and is performed with the help of RNA polymerase enzyme as follows:
i. Initiation- the process of transcription initiates at the promoter site in the transcription unit with the help of sigma factor of RNA polymerase.
ii. Elongation- the structural gene (template strand) is transcribed to RNA.
iii. Termination- the process of transcription gets terminated at the site of the terminator region which is towards the 3' end of the coding strand of DNA, where RNA polymerase encounters the rho factor.
The transcribed RNA gets released and DNA gets its double helix structure back again.
Hence, it can be concluded that the chain-like structure (A) in the image given above is the polynucleotide chain of RNA which is transcribed from the structural gene of the transcription unit.
The big oval structure (B) located towards the 3’ end of the coding strand is the RNA polymerase enzyme which encounters the rho factor (small oval structure C) and terminates the process of transcription.
Therefore, A-RNA, B-RNA polymerase, C-Rho factor are the correct match for the given image in the question.