Final answer:
The emerging megalopolis in Latin America is Option D: Mexico City, Sao Paulo, Rio de Janeiro.
Step-by-step explanation:
The emerging megalopolis in Latin America is Option D: Mexico City, Sao Paulo, Rio de Janeiro. These three cities, along with their urban neighbors, anchor the core economic area in the south of the continent. They are growing rapidly due to internal migration and serve as major centers of economic activity and business opportunities.