The first naturalization law in the united states in 1790 limited citizenship to "free white persons," which set up a relatively broad and inclusive definition of "whiteness." however, the definition of whiteness narrowed such that it applied only to anglos by the early twentieth century. what social change led to this increasingly exclusive definition of whiteness?
a. the surge in immigration of non-anglo europeans to the united statesb. the migration of african americans from the south to the northc. the establishment of the one-drop ruled. the supreme court's 1896 plessy v. ferguson decision

The answer is a. the surge in immigration of non-Anglo Europeans to the United States

Explanation:

The first statute in the United States to codify naturalization law. Alternately known as the Nationality Act, the Naturalization Act of 1790 restricted citizenship to "any alien, being a free white person" who had been in the U.S. for two years. In effect, it left out indentured servants, slaves, and most women. This led to an influx of immigrants from East and South Europe.

i believe the answer is:   psychological  experiment

in this experiment, wilhelm wundt became the first person that implement scientific method in analyzing the pyschological phenomenon.

due to this result, wilhelm wundt also able to make psychology to be acknowledged as a separate scientific field from biology.

the values of the selma marchers was to bring   their ability to vote into law. mlk was not hat march, which was protesting toward lbj