What group of people did nativists support

Native americans

Explanation:

Nativism is the political policy of promoting the interests of native inhabitants against those of immigrants,

Nativism is the political policy of promoting the interests of native inhabitants against those of immigrants, including by supporting immigration-restriction measures. In scholarly studies "nativism" is a standard technical term. Those who hold this political view, however, do not typically accept the label.

D

Explanation:

Although it was not a formal alliance, Russia moved to defend Serbia against Austria-Hungary