Answer: All the statement are correct.
Explanation:
In prokaryotes, an operon are unit of transcription regulation, operon are functioning unit of DNA of which consists of cluster of related genes with a single promoter and an operator.
The structural genes in the operon are either all ON or OFF at the same time, because they are controlled by a single promoter and an operator. Represible or inducible operon are all turned of off unless needed.
The DNA of an operon are generally transcribed into a single mRNA molecule which is polycistronic that codes for more than one protein