According to the map, in early 1900s, a) the united states became a more diverse nation b) the united states became a less diverse nation c) only people from europe moved to the united states d) only people from asia moved to the united states (look at picture)

A) the United States became a more diverse nation.

Explanation:

According to this picture, during the early 1900s, the United States welcomed a large number of immigrants from all over the world. Immigrants came from every continent, looking for better opportunities for themselves and their families. The addition of immigrants to the American population resulted in a more diverse nation.

the roman army grew in size and became dominant in the mediterranean region.

"a government in which power is divided between state and national levels". federalism is a system of government in which entities such and state and province, share power with the national government.