Because "Where is China at the end of the world" means to lament that China's land was divided by foreign powers, and China's land was divided into pieces overnight, so it laments that "everything in the world is China's land".

2. The second way is also D.

Because closing the door to the outside world means that the Qing government closed the door to the outside world, did not communicate with other countries, thought itself to be a "land of abundance" and despised advanced technology. This situation has existed since Emperor Kangxi. Although he allowed a few missionaries to enter China, in essence, China has been closed to the outside world since Emperor Kangxi.

As for "seeing the world", it refers to Wei Yuan. Because the Qing government at that time was mediocre and incompetent, many people with lofty ideals opened their eyes and advocated learning advanced foreign technology. Wei Yuan was the earliest and most famous, so he was chosen.