What pull factors and push factors prompted people to move to the united states in the late 19th and early 20th centuries?

There are a lot of factors that prompted the people to move to the United States. One of it is overpopulation. Others wished to escape economic problems brought on by poor harvests, unemployment due to increased mechanization, the failure of local industries, and other factors. Push factors encourage people to leave their home and settle elsewhere while pull factors attract migrants to new areas. During this time the greatest pull factor is high unemployment while the abundance of jobs for the citizens is an effective pull factor. Another Pull factor known is the growing economy but the state has a small population of residence absorbs a large number of immigrants during the early decades of the 19th century.

The answer is d. spain.