Which of the following scenarios is the most likely mechanism by which RNAi silences the expression of genes?

A. RNA binds to an mRNA strand before it reaches the ribosome, thereby preventing translation.

B. RNA binds to an mRNA strand after it leaves the ribosome, which prevents translation.

C. RNA binds to helicase, which prevents DNA replication and thereby the expression of the gene.

D. RNA binds to DNA, which prevents transcription.

E. RNA binds to RNA primase, which prevents the transcription of the gene.

RNA interference (RNAi) is a mechanism in which antisense RNAs or small interfering RNAs (siRNAs) interfere with gene expression by binding to mRNA, preventing translation and protein synthesis. When siRNA enters the cell, it binds to a protein complex called Dicer, which dices up siRNA into smaller fragments. One strand of these fragments, typically the antisense strand, is loaded into another protein complex called the RNA-induced Silencing Complex (RISC), which destructs the mRNA to silence gene expression.

Learn more about RNA interference (RNAi) here:

https://brainly.com/question/44004169