There are many famous cultural relics in our country many thousands of years ago.A. dati

问题补充：

There are many famous cultural relics in our country, many thousands of years ago.

A. dating back to

B. date back to

C. dated back to

D. were dated back to

答案：

(答案→)A. dating back to

B. date back to

C. dated back to

D. were dated back to

解析：句意：我们国家有很多文化遗迹，很多要追溯到几千年前。这里前面是简单句，因为中间没有连词，所以逗号后面不是句子，而是独立主格结构，用逻辑主语+非谓语动词构成，因为date back to“追溯到”这个词组没有被动语态，所以用现在分词，所以选A。