The answer is the axis. The earth rotates on the x-axis and moves on the y-axis.
I know the answer is C because the Three Gorges Dam is located in China.
1. Zygote
2. Sporophyte
3. Gametophytes
4. Gametes
I'm not really sure how to explain how they are related other than they make up the reproductive system (the obvious).
Hope this helps, in a way. (:
This is something that I used I found it when I was asking the same question myself