Final answer:
C. To promote democracy and weaken European colonial powers.
Great Britain supported Latin American revolutions to open new markets for its products, while the United States aimed to promote democracy, minimize European influence, and support commerce.
Step-by-step explanation:
The primary reasons that Great Britain and the United States supported Latin American revolutions were C. to promote democracy and weaken European colonial powers. Great Britain saw the newly independent Latin American regions as potential markets for their industrial products.
On the other hand, the United States was sympathetic to the revolutions in Latin America, recognizing the new governments to reduce European influence, promote commerce, and encourage the spread of republicanism. Furthermore, American leaders were concerned about maintaining the independence of the new republics and feared other European powers might try to establish their influence if Spain's hegemony was ousted.