The correct answer is **C. a decline in jobs for citizens**.
The Immigration Act of 1924, also known as the Johnson-Reed Act, was passed in response to a fear that immigration was leading to a decline in jobs for American citizens. The act set quotas on the number of immigrants who could be admitted to the United States from each country, with the goal of preserving the country's "racial and national homogeneity."
The other options are not as accurate explanations for why the Immigration Act was passed. **A fear of overseas wars** was not a major factor in the passage of the act. **A decline in wages for citizens** was a concern for some people, but it was not the primary reason why the act was passed. **A fear of communism** did not become a major factor in American politics until the late 1940s.
Here are some other reasons why the Immigration Act of 1924 was passed:
* A belief that immigrants were taking jobs away from American citizens.
* A belief that immigrants were not assimilating into American culture.
* A belief that immigrants were a threat to the country's national security.
The Immigration Act of 1924 was a major turning point in American immigration policy. The act's quotas remained in place for over 40 years, and they had a significant impact on the makeup of the American population.