There was no significance of Rappe of Nanking. they just want to show what power they though they had.
First answer is B because it moves because of heat, and you could probably assume.
2nd is C, obvious
3rd St Helens, the rest arent on the map
4th My best guess is changing
claim territory
secure gold (and goods)
life in Spanish colonies
decline of the Spanish empire
The answer to your question is C.