The statement that accurately reflects an important reason why intraregional migration occurred in Latin America after 1945 is:
Megacities became desirable living destinations for many Latin Americans.
This trend was largely driven by the search for better economic opportunities, improved living conditions, and access to services that megacities offered. While the other options touch on relevant points, the rapid urbanization and attraction of large metropolitan areas are particularly significant in the context of migration patterns in Latin America during that period.