Answer:
D. Diseases spread more rapidly around the world as human contact
between regions increases.
Step-by-step explanation:
International air travel is causing pandemics to spread. Today, in many countries, especially in sub-Saharan Africa, educational achievement is threatened by the HIV / AIDS pandemic, which has claimed the lives of many trained teachers, mostly female teachers, in both primary and secondary schools. The immunodeficiency virus existed in the thirties of the last century, but only the construction of large transit highways in the tropical forests of Africa led to the spread of AIDS not only in the tropics, but also in other parts of the world. Ebola, SARS, swine flu - outbreaks of these infections occur again and again, but only since even the most distant points of the planet are connected to global transport networks, epidemics are no longer a locally limited phenomenon.