What is the background of the origin of China traditional opera?

The origin of traditional operas in China can be traced back to ancient times, and primitive songs and dances are the embryonic state of traditional operas in China. The direct source of Yuan Zaju mainly comes from two aspects: one is the rap art "Zhu Gong Tune" from the Song Dynasty to the Jin Dynasty, and the other is the short play "Song Zaju Jin", which focuses on teasing.