Answer:
The correct answer is D. A major cause of imperialism in Africa after 1870 was Europe's desire for access to raw materials.
Explanation:
During the second half of the 19th century, a new political theory developed in Europe, mercantilism, which advocated closed economies based on the accumulation of capital and material goods. This made the European powers seek to expand their markets for raw materials, in order to control them and thus obtain more capital through their commercialization.
As the American and Asian continents were already colonized, the European powers set their sights on Africa, a territory overflowing with raw materials and without a clear colonial dominator. This is how the Berlin Conference arrived, where the territories controlled by each European power were delimited.
