In prokaryotic operons, three types of regulatory molecules can affect gene expression. Match each molecule to its described role.

1. There are three types of regulatory molecules that affect operon expression in prokaryotic cells. 2. Repressors are proteins that suppress transcription in response to an external stimulus. 3. Activators are proteins that increase transcription in response to an external stimulus. 4. Inducers are small molecules that either activate or repress transcription depending on the needs of the cell and substrate availability. 5. The option reversing repressor and activator roles contradicts their defined functions. 6. The option claiming inducers have no effect ignores their defined role of activating or repressing transcription as needed. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 16 "Gene Expression", section 16.2 Prokaryotic Gene Regulation_