春秋战国时期，新旧制度更替，社会大变革，其根本原因是（    ）

传承文化薪火　滋养文化基因

材料一某校思想品德教师为弘杨中华民族传统美德，落实优秀传统文化进课堂，带领学生开展“传承优稚如瓷的文化基因”主题阅读活动，让大家推荐自己喜欢的传统经典作品。

材料二为传承中华文明的薪火　滋养民族文化的基因，某学校组织了以下系列活动。

    Rose's mother wants to take Rose to the zoo today. Many kinds of animals are in the zoo. So Rose is very happy.

    Rose and her mother go to see the tigers and lions first. Tigers and lions are scary so they lives in strong cages in the zoo. And they eat much meat every day.

    Rose sees two big elephants and a baby one. The elephants are very kind to people. Rose rides on an elephant and she is glad.

    Some cute pandas are in the zoo, too. They are a little shy. So people need to be very quiet when they go near them. Look! Five giraffes are there. They have long necks. They are from Africa(非洲). They like eating grass and leaves very much.

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