An operon yields a single polycistronic mRNA transcribed from one promoter that coordinates multiple genes.

• A. False
• B. Sometimes
• C. True
• D. Never

Answer: (C)

In bacteria, operons coordinate the expression of genes that function together by using a single promoter to drive transcription of one polycistronic mRNA. This means one transcript contains multiple coding sequences, and ribosomes translate each segment to produce several proteins that operate in the same pathway. The lac operon is a classic example: one promoter yields an mRNA that includes lacZ, lacY, and lacA, and these enzymes are produced together when the operon is active.

Because the statement describes this exact setup—one promoter producing a single polycistronic mRNA that coordinates multiple genes—it aligns with the standard operon model. Exceptions exist in biology, such as operons with internal promoters or alternative transcripts, but the core arrangement is accurately captured here. Hence, the answer is true.