Who enunciated the idea of myth as depoliticized speech in bourgeois society?

The correct option is Roland Barthes.

This concept was introduced by the French literary theorist and philosopher Roland Barthes in his seminal 1957 book titled Mythologies.
In this work, Barthes analyzes how modern myths are constructed and function in bourgeois society.

According to Barthes, myth is a type of speech or a system of communication. He argues that myth takes historically and politically constructed meanings (which serve the interests of the dominant bourgeois class) and strips them of their historical context. By doing so, myth naturalizes these values, making them appear self-evident, universal, and common sense.
This process of making historical or political realities seem natural is what Barthes refers to as "depoliticized speech." Instead of appearing as a political choice or ideology, the myth makes the bourgeois world view look like the natural order of things.