Answer: C. He drove out invaders and united England around a single leader.
Alfred the Great was King of Wessex from 871-886 and King of the Anglo-Saxons from 886-899. After Alfred took the throne, he dealt with many Viking invasions, until he created Danelaw in the north of England, which reduced conflict between Vikings and Anglo-Saxons. He eventually became the dominant ruler in England, uniting the country. He encouraged education, the legal system, military structure and improved the people's quality of life.
James Monroe was the 5th president
It was invented by the Sumerians, so it would be Sumer
I believe the answer is the Ohio river.