The correct answer is a) some Africans struggle to get clean drinking water.
Desertification can lead to the degradation of land and water resources, making it more difficult for communities to access clean drinking water. The other options do not accurately reflect the effects of desertification in Africa. Desertification does not lead to the development of highly developed infrastructure or the rapid growth of rainforests, nor is it directly responsible for political instability across the majority of Africa.