What is the most popular song by System of a Down?

The most popular song by System of a Down is "Chop Suey!" from their second studio album, Toxicity. Released in 2001, the song became a critical and commercial success, with its distinctive blend of aggressive guitar riffs, pounding drums, and Serj Tankian's impassioned vocals. "Chop Suey!" was widely played on radio stations and became one of the band's signature songs, contributing to their rise in mainstream popularity. It has since been featured in film, television, and video game soundtracks.