Charlemagne was known as”the father of Europe”. How does this map help to explain that title
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The correct answer is alternative D) It shows that Charlemagne conquered a huge part of Europe.
Charlemagne is considered the Father of Europe because he united most of Western Europe, and was the first to do so after the Romans. Furthermore, he ruled parts of Europe that had never been ruled by Franks before.
The map shows how much of Europe he actually conquered, and according to it, we can see that he conquered pretty much Western Europe as a whole. For this reason, alternative D is the correct one.