Final answer:
A major pull factor attracting immigrants to the United States between 1830 and 1850 was the hope for economic opportunities amidst America's industrial expansion, with the promise of employment and the American Dream serving as strong attractions. The correct answer is option 2.
Step-by-step explanation:
A major pull factor that brought immigrants to the United States between 1830 and 1850 was the hope of economic opportunities due to America's industrial growth. As industries and the construction of the transcontinental railroad surged, the need for labor increased significantly. This drew people globally, particularly those looking to improve their livelihoods, achieve financial success, and escape from various hardships in their home countries. Such factors are understood as 'pull' and 'push' factors, where 'pull' factors are the appealing aspects of a destination that attract people, such as job opportunities, while 'push' factors are adverse conditions that drive people to leave their home countries, like famine, religious persecution, or political unrest.
During this era, many Europeans left their agricultural or nonindustrialized regions in search of better living conditions and the possibility of upward mobility, known as the American Dream. Among these were Germans fleeing political unrest and Irish escaping the Great Famine. These groups, and others that followed, were drawn to the promise of consistent work and the potential to establish a better life for themselves and their families in the U.S.
In conclusion, the notion of achieving the American Dream through hard work and the presence of abundant job opportunities were significant pull factors that attracted a large influx of immigrants to the United States in the first half of the nineteenth century.