Biology

The correct answer is: D.They stimulate the expression of certain genes.

Cell signals play a crucial role in stimulating the expression of certain genes. These signals, like hormones or growth factors, bind to receptors on the cell surface or within the cell. This triggers intracellular signaling pathways that either activate or repress gene transcription. This regulation allows cells to adapt to environmental changes and control processes like growth, differentiation, and metabolism.

Other options are less relevant:

A.Preventing gene activation: While some signals may repress gene expression...