So that they would own a majority of Europe and not have to have there countries bordering each other.
Answer:
A. The empires at this time had a fairly low status as they were unable to unify under Christendom and the Pope. Even with all the land the European nations owned the Mongols captured a greater area in far less time. This could have influenced Well's decision on saying it was without parallel.
C. The Golden Horde Mongol khanate is a good way to support Wells' description. The Mongols had invaded Russia and they bowed down and decided to help them. The Russians had seen what they were doing to other countries and decided they would gain more from just assisting the Mongols instead of trying to fight them off.
I apologize for not having an answer to part B, I couldn't figure that out myself.
Answer: The invasion, consisting of two distinct campaigns, was ordered by the Persian king Darius the Great primarily in order to punish the city-states of Athens and Eretria. These cities had supported the cities of Ionia during their revolt against Persian rule, thus incurring the wrath of Darius.
Explanation:
This would be an example of "chronological history", since the evens are being "placed" in the order in which they occurred. This is often helpful to understand "cause and effect" relationships.
Sphere of influence an outside claims trading privileges and protectorate have their own government