Answer:
The reasons of the rise of nativism in the 1920s and 19030s were the increase of immigrants, the call of the citizens arguing the loss of access to opportunities and the bigger difficulties they suffered due to the competitive environment.
Explanation:
In the first place, Nativism is the sociological and political position and posture of looking to provide opportunities to national born citizens instead of immigrants.
In the second place, it became a very big movement and phenomenon in the early 1920s and 1930s because U.S. citizens encountered difficulties to cover the needs. As a consequence, they started to ask for help to the government and their voice was heard.
The government strengthened laws to provide its citizens the security they needed to satisfy their needs and approved laws to measure the number of immigrants and the type of immigrants that arrived in the U.S.
It was an effort of both sides to help citizens find they help they argued to need and not been left alone on their luck.