Which consequence of the Columbian Exchange significantly reshaped global demographics?

• A. Spread of diseases to the Americas and introduction of new crops to Afro-Eurasia
• B. The immediate end of slavery
• C. The invention of the printing press
• D. The decline of long-distance navigation

Answer: (A)

The main idea here is how the Columbian Exchange altered population patterns around the world. When Europeans arrived in the Americas, deadly diseases such as smallpox and measles spread to Indigenous peoples who had no prior exposure, causing enormous population losses and upheaval. This demographic collapse helped clear land for colonization and the growth of new plantation economies. At the same time, crops from the Americas like maize and potatoes began spreading to Afro-Eurasia, providing more calories and supporting larger populations over time. This combination produced a dramatic shift: sharp declines in the Americas and population growth in Europe, Africa, and Asia. The other options don’t capture this global-scale population rebalancing, as they involve developments not tied to such widespread demographic outcomes.