Question

what did not cause many immigrants to leave their native countries?

crop failures

political unrest

harsh climate

poverty

Explanation:

Crop failures, political unrest, and poverty are common "push factors" that drive immigration as they create hardships (lack of food, unsafe environment, economic struggle). Harsh climate is less of a direct, widespread driver for mass immigration compared to the others, as people often adapt or climate changes are less immediate in forcing migration on a large scale relative to the other options.

Answer:

C. harsh climate