What is the earliest extant Buddhist scripture in China?

The earliest existing Chinese Buddhist scriptures are forty-two chapters. According to the book "On Reasoning and Confusion" by Mou Rong in the Eastern Han Dynasty, it is said that in the seventh year of Han Yongping (64), the Jin people dreamed of flying to the temple, so they sent 12 messengers to the western regions to visit the Buddhist countries. In the 10th year of Yongping (67), he returned to Luoyang with Indian monks Kaya Morten and Zhu Falan, brought back scriptures and Buddha statues, and translated 42 chapters. This scripture consists of 42 short Buddhist scriptures, so relevant scholars have verified that it is not a directly translated scripture, but a "scripture transcript" that compiles a variety of scriptures. The Chinese version of Forty-two Chapters Classic mainly expounds the basic teachings of early Buddhism. Because its content was simple and plain, it was more suitable for the needs of Buddhist beginners when Buddhism was first introduced to China, so it was very popular in the society at that time. There are now three versions of Forty-two Chapters Classic: one is Xiao San's manuscript, which was opened in the early years of the Northern Song Dynasty; One is an annotated version of North Song Zhenzong, which was included in Yongle Nanzang in the Ming Dynasty; There was also an annotated version of Shousui in Song Dynasty, which was widely circulated, and there were monks' annotations in Ming and Qing Dynasties.