The correct answer is Believed immigrants from certain places of origin could not absorb American values
The Know-Nothings movement was a Native American political movement of the 1850s. It began as a popular reaction to the fear that large cities were being flooded by Irish Catholic immigrants whom they considered hostile to American values and controlled by the Pope in Rome.
The answer is A because the significance of gunboat diplomacy is military threats which is a foreign policy used to scare the less powerful nation so that they follow the most powerful nations demands.