In terms of social structure, what term describes the general populace in ancient Rome?

The term that best describes the general populace in ancient Rome is "plebs humilis." This phrase translates to "low plebs" and is often used to refer to the lower class of Roman citizens who did not possess significant wealth or political power. The plebs humilis were largely composed of free citizens who worked as laborers, tradespeople, and farmers, and they played an essential role in the economy and social fabric of Rome, although they often faced social and economic challenges compared to the wealthier classes.

In contrast, the other terms do not apply to the general populace specifically. "Ingenui" refers to freeborn citizens, which includes individuals from both higher and lower social standings, thus lacking the specificity of describing the general lower class. "Augustales" were a group of priests dedicated to the worship of the emperor and his family, focusing on a specific religious and social role rather than the broader populace. "Megalography" pertains to the genre of large-scale illustrations or artwork rather than defining any aspect of societal layers in Rome. Therefore, "plebs humilis" accurately represents the lower strata of Roman society.