In an African Studies Research Paper That You Are Writing

In an African studies research paper that you are writing for publication, you use the word "culture" to refer to a group of South African people.Which of the following is a challenge to using "culture" to define a group of South Africans?

A) South Africans are likely very different from people who live in parts of North Africa.
B) Present-day South Africans are likely very similar to South Africans in the early twentieth century.
C) All South Africans share the same political and environmental contexts, leading them to have very similar experiences.
D) There is too much variability within the South African population to warrant a single "South African" category.
E) South Africa is economically very different from its neighbor, Botswana.