Which of the following statements best defines the term operon? a. an operon is a region of rna that consists of the coding regions of more than one gene. b. an operon is a region of dna that consists of a single gene regulated by more than one promoter. c. an operon is a region of dna that codes for a series of functionally related genes under the control of the same promoter. d. an operon is a region of dna that codes for sugar-metabolizing enzymes.

The correct answer is: c. An operon is a region of DNA that codes for a series of functionally related genes under the control of the same promoter.

Operons contain cluster of genes that are transcribed together into mRNA or are not expressed at all. Formed mRNA undergos splicing to create monocistronic mRNAs so that can be translated separately. Operons are more often found in prokaryotic cells but it can appear in eukaryotic cells and in viruses.  

the correct answer, according to e2020, is the second choice there is an occluded front in region a and a cold front in region b.

b a mature ovary of a plant.