Which of the following statements best describes the function of RNAi?

• A. Small RNA molecules interfere with translation by targeting ribosomes for degradation.
• B. Small DNA molecules interfere with mRNA molecules by blocking their ability to bind to a ribosome.
• C. Small RNA molecules interfere with translation by targeting specific tRNA molecules
• D. Small RNA molecules interfere with translation by blocking a target mRNA's ability to bind to a ribosome.

Answer: (D)

Verified step by step guidance

1. Understand that RNA interference (RNAi) is a biological process where small RNA molecules inhibit gene expression or translation.
2. Recognize that RNAi primarily involves small RNA molecules such as small interfering RNA (siRNA) and microRNA (miRNA).
3. These small RNA molecules bind to complementary sequences on target mRNA molecules.
4. Once bound, they prevent the mRNA from being translated into proteins by blocking its ability to bind to ribosomes.
5. Thus, the correct description of RNAi's function is that small RNA molecules interfere with translation by blocking a target mRNA's ability to bind to a ribosome.