Art is created by the people and cannot be separated from people's lives. In the people's social life, economic factors are a very important factor. It is difficult to imagine how people's social life would look without economic factors. It is also difficult for us to imagine how art without the participation of the people's economic life can be developed. In terms of opera, it was formed in the Song Dynasty. In addition to various factors, it is also closely related to the increasingly commercialization of the performing arts market in the Song Dynasty. Relationship. It can be said that this is an important reason for the formation, survival and development of opera. "This" in the last sentence refers to:. ['Social life of the people.', 'The artistic life of the people.', "People's economic life.", 'Popularization of opera art.']