Which of the following is the best example of imperialism? A. In 1776, the United States declares independence from Britain.
B. The territory of Utah becomes a US state in 1896.
C. Belgium and Luxembourg form an economic union in 1921.
D. In 1902, Britain wins the South African War and takes over the Transvaal.

D

Explanation: The word imperialism means “a policy of extending a country’s power and influence through colonization, use of military force and other means”. This is exactly what happened at the South African War.
The Boer South African Republic (Transvaal) wanted independence - maintain their cultural style, religious beliefs, own language and their way of life - but Britain had interests in that area - especially the gold mines. This is all classic imperialism traits.