We began to adopt the twenty-four solar terms that are beneficial to the farming season.

Taichu calendar began to adopt 24 solar terms that are beneficial to farming season.

The book Huainanzi records 24 solar terms that are exactly the same as those in modern times. In A.D. 104, taichu calendar Law officially set 24 solar terms in the calendar, and defined the position of the 24 solar terms in the astronomical calendar.

A. taichu calendar, B. Shi Gan's Classic, C. Five Elements of Han Dynasty, D. Da Yan Li.

Answer a.

Analyze this topic and examine literary common sense. Item A: taichu calendar law divides a day into 81 days, so it is also called "81 calendar". It is a relatively complete calendar in ancient China and an epoch-making progress of our calendar. We began to adopt the twenty-four solar terms that are beneficial to the farming season. Item a is correct.

Item B: Shi Gan Xing Jing is an astronomical monograph, which consists of eight volumes of Gan Jing and sixteen volumes of Shi Jing, and was roughly written in the Warring States Period. Shi Gan Jing is two books written by Gan De, a native of Qi, and Shi Shen, a native of Wei. Gander wrote eight volumes of astronomy, and Stone God wrote eight volumes of astronomy. Together, these two books are called The Shi Gan. Item b is wrong. Item C: Hanshu, also known as Pre-Hanshu, is the first biographical chronology of China, and one of the "Twenty-four History".

Records of the Five Elements, compiled by Ban Gu, a historian in the Han and Eastern Han Dynasties, is one of the "records" in history books. Han Bangu wrote Han Shu, which has five volumes. Record solar eclipse, lunar eclipse, star variation and various disasters, as well as the theory of yin and yang. Later, the official history of the dynasties followed. Item c is wrong. Item D: Dayan calendar, also known as Kaiyuan Dayan calendar, has been implemented for 29 years since the 17th year of Kaiyuan in the Tang Dynasty (AD 729). One line. It is named according to the legislation of image number in the Book of Changes. Item d was not elected. Therefore, choose option a.