Final answer:
European colonial powers limited economic opportunities for Africans in the early 20th century through exploitative economic policies, including land expropriation, exploitation of native labor, and exclusion from international trade.
Step-by-step explanation:
In the early 20th century, European colonial powers limited economic opportunities for Africans by implementing exploitative economic policies. They expropriated land from Africans, seized raw materials like rubber, and exploited native labor through forms of slavery and forced labor. Africans were also excluded from participating in international trade, preventing the development of a wealthy capitalist class.