Final answer:
Tecumseh and other Native Americans joined the British in the War of 1812 because they feared losing more land through American expansion, hoped to regain their lost lands, and recognized Britain's superior naval power. The correct answer is option C. and D.
Step-by-step explanation:
During the War of 1812, Tecumseh and other Native Americans joined the British for several reasons. One reason was that they feared an American victory would lead to further loss of their land through expansion. They believed that supporting Britain might give them a chance to regain their lost lands. Additionally, the British were seen as a greater naval power than the United States, which made them attractive allies.