Before the So-Called Scramble for Africa, How Much Land in Africa

Before the so-called scramble for Africa, how much land in Africa had Europeans claimed?

A) Europeans had laid stake to less than 1 percent of African lands because few explorers had ventured there.
B) Well before the "scramble," Europeans were heavily invested in African affairs and owned about 70 percent of the land.
C) Only the Portuguese had laid any claims to land in Africa, which amounted to no more than 5 percent.
D) Europeans had claimed over 90 percent of Africa following the end of the slave trade because they were already so well-versed on the region.
E) Europeans claimed less than 10 percent of Africa and were relatively inactive in the regions.