Wanted to avenge the defeat of his dad xerxes
Answer:
The North European Plain
Explanation:
The North European plain is the most populated region of the four mentioned in the question.
This was not always the case, and until the Middle Ages, the North European Plain was sparsely populated. However, ever since, its population has been growing, because despite having a climate that is wet and cool the majority of the year, the soil is very fertile, and the lack of physical geographical barriers makes it easier for human dwelling.
The above system of United States Constitution is showing three organs of the state i.e Legislative branch, Executive branch and the Judicial branch.
And below each division, their works are given. Aswecan were that, each of the organ is at same height which shows that they are practicing equal powers and they don't interrupt in each others work.
They practice the system of <u>Checks</u><u> </u><u>and</u><u> </u><u>Balances</u> to ensure that none of the organ is enjoying and grabbing too much.
So, the most appropriate option is:

Checks and balances system.
And, we are done !!
#CarryOnLearning...
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Profited from new trade routes and large supplies of gold<span />
( a ) european imperialism and american expansionism overseas