Which of the following groups experienced the most significant growth in immigration during the late 19th century?

The significant growth in immigration during the late 19th century is primarily attributed to Eastern Europeans. This period, particularly from the 1880s to the early 1900s, saw a wave of immigrants from countries such as Poland, Russia, and other parts of Eastern Europe, driven by various factors including economic hardship, political unrest, and the pursuit of better opportunities in the United States.

Eastern European immigrants often faced harsh living conditions and persecution in their home countries, prompting many to seek refuge and a fresh start in America. They contributed to the growth of urban labor forces, working in factories and helping to build infrastructure. This demographic shift not only increased the population but also transformed the cultural landscape, as Eastern Europeans brought diverse customs and traditions, which enriched American society.

In contrast, other groups listed either did not experience the same level of immigration during this time or were involved in different trends of movement. Southern Africans, for instance, faced colonial and local socio-political issues, while Central American immigration grew more significantly in later decades. Additionally, Middle Eastern immigration was comparatively less prominent until the early 20th century. Thus, Eastern Europeans indeed represent the correct answer due to their substantial numbers and the timing of their migration.