Which factor was NOT a cause of imperialism?

The correct answer is D, Environmental Conservation. This factor stands out because environmental conservation typically emphasizes the protection of ecosystems and natural resources, which is fundamentally at odds with the motives of imperialism. Imperialism often involved the expansion of a nation's territory and influence, primarily driven by the pursuit of economic gain, military power, and a belief in national superiority over others.

In contrast, the other factors listed—economic benefits, military strength, and national superiority—were significant drivers of imperialism. Economic benefits prompted nations to seek new markets and raw materials, fostering expansion into new territories. Military strength was essential for establishing and maintaining control over those regions, ensuring security and dominance. National superiority reflected a belief in the moral and cultural justification for dominating other peoples, often framed as a civilizing mission. Thus, environmental conservation does not align with the aggressive expansionist policies characteristic of imperialistic endeavors.