阅读下面短文,从每题所给的A、B、C、D四个选项中选出最佳选项。After four months of digging, the Ningbo Cultural Heritage Research Institute shared what they found at the Malangxia site (马廊厦遗址) on August 29. The exciting discovery in Yuyao, Zhejiang Province, China, has helped us learn more about how people lived and how society changed over a very long time.
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The site is 2,000 m2 big, and 102 things were found like ash pits (坑), houses, tombs (坟墓), and roads. They were made in the middle and lower parts of the Changjiang River area. Imagine digging up layers (层) of history like layers of cake! The Malangxia Site has five different layers, and each one is like a different chapter in a book, telling us about a different time period.
The first layer is from the Shang-Zhou dynasties, and we found a special tomb. As we move up to the next layer. Here, we found lots of cool things like houses, pits, tombs, and roads. They are like photos that record the life at that time. The third isn't as full as the others. We only found one tomb. But the fourth layer has a lot of findings, with pits, tombs and holes. These things show us how art styles from the north and south of China mixed together.
Local experts say that the Malangxia Site is the biggest and best-kept archaeological (考古的) site in Yuyao so far. It's like a treasure box full of history that helps us understand how society changed over thousands of years. It's amazing to think that just by digging, we can learn so much about people who lived long ago!