In the late 1800s, imperialist countries often used their colonies as a) sources of labor for their factories. b)sources of manufactured goods. c)markets for their natural resources. d)markets for the products they produced.

The correct answer is D, as in the late 1800s, imperialist countries often used their colonies as markets for the products they produced.

The imperialist powers were among the most industrialized countries, and used their colonies as a source of natural resources. One way to locate their products was to sell them in the colonies, which were taken away of any possibility of technological or industrial development.