Final answer:
The most logical reason for Africa's population growth is higher birth rates, influenced by cultural norms, fertility rates, and a young demographic distribution. Healthcare improvements and urban migration also play roles in the population increase. The correct option is A.
Step-by-step explanation:
The most logical reason for Africa's population growth is higher birth rates. This is observed through the continent's high fertility rates, which are significant compared to the rest of the world. The United Nations Population Fund categorizes countries according to their fertility levels and predicts that populations in high-fertility countries, mainly located in sub-Saharan Africa, will likely triple between 2011 and 2100. This growth is in stark contrast to low-fertility countries where populations are expected to decline.
In regions such as Europe and North America, population growth is minimal or negative, attributed to lower birth rates and aging populations. Africa's sustained high fertility rate is influenced by several factors, including cultural norms, lower availability of family planning resources, and in some areas, a lack of education and empowerment for women. Moreover, the young demographic distribution of the population fuels a phenomenon known as 'population momentum,' where a large base of young people leads to continued high fertility even if the birth rate per woman begins to decline.
Other factors contributing to Africa's population increase include declining mortality rates due to improvements in healthcare and a reduction in the impact of diseases like HIV/AIDS. Urbanization and rural-to-urban migration in search of employment opportunities are also causing rapid expansion in urban areas, changing the population dynamics and further influencing growth patterns. While the availability of land, reduction in casualties from wars, or immigration rates may also have an impact, they are not considered the primary drivers of Africa's population explosion.