Final answer:
In the 1840s, a substantial number of Irish immigrants arrived in the United States, facing initial hostility due to their Roman Catholic faith in a largely Protestant country. Over time, they assimilated and significantly influenced American society. The question about the specific percentage of Irish-born individuals among the foreign-born population in the 1840s cannot be answered with the provided information. so, option A is the correct answer.
Step-by-step explanation:
The period of the 1840s in the United States was marked by significant immigration, especially from Ireland. The Irish-born population in the U.S. faced challenges when they first began migrating in large numbers during the 1840s and 1850s due to the largely Protestant composition of the United States, which was not welcoming to Roman Catholic newcomers. However, by the second half of the nineteenth century, Irish immigrants and their descendants had made considerable strides in integrating into American society. Despite initial rejections, by 1890, over 80 percent of the population of New York was either foreign-born or children of foreign-born parentage, illustrating the profound impact of immigration on the city.
Irish immigrants in the 1840s did not make up a specific percentage of the foreign-born population, but their numbers were substantial and their arrival was part of a wave that would ultimately shape the composition and culture of the United States. It is important to note that over time, the hostility they initially faced diminished, and Irish-Americans became an integral part of the nation's business, political, and social fabric.