I believe it is isolation
Fundamentalism and nativism had a significant affect on American society during the 1920's. Fundamentalism consists of the strict interpretation of the bible. This was especially relevant for those who were considered Christians. These fundamentalists used the bible to guide their actions throughout the 1920's. A perfect example of this would be the increased amount of charity work done by Christians to help the urban poor. Creating Sunday schools for children and providing shelter/food shows how they interpreted the importance of service based on the reading of the bible.
Nativism, on the other hand, focuses on the idea of "Americans first." Nativists greatly disliked immigrants, as they felt they were stealing job from native born Americans (hence the name, nativists). This caused a sense of fear and paranoia in American society. The first Red Scare and the court case of Sacco and Vanzetti are perfect examples of how "un-American" views caused American citizens to act irrationally towards people from other countries.
The correct answer to this open question is the following.
Although there are no options provided, we can say the following.
Romans were able to move from wooden houses to more permanent structures because they started to experiment with the use of concrete, cement, and better formulas to increase the quality of this material. Romans were also capable of exploring new ideas to create forms such as vaults and arches. Let's have in mind that Romans originally used a different material called "tufa" which was a volcanic rock. A solid material but not an aesthetical one. Years later, Romans cold mix concrete with volcanic sand to create a more resistant material. With the use of marble, Romans were capable of creating marvelous buildings and temples.
