Answer:
(D) The Vikings gained some land, but were eventually defeated by European forces.
Step-by-step explanation:
Vikings were very influential warriors in Europe and were feared because of their violent and bloody invasions across the continent. In fact, the Vikings conquered many lands, but were defeated in the battle of Edington in 878, in a battle against the army of King Alfred, at the same time the leader of the Vikings Guthrum converted to Christianity.
After that, looting and trespassing became less and less profitable causing the Vikings to ask for influence.