Final answer:
The statement that Europeans had no interest in Africa is incorrect; they had interests related to resources and the slave trade but were hindered by diseases like malaria, difficult geography, and African resistance.
Step-by-step explanation:
The correct answer to the question "Which of the following was NOT a reason that prevented Europeans from conquering Africa early on?" is option A: Europeans had no interest in Africa. Throughout history, Europeans did have an interest in Africa, primarily for resources such as gold in the early days and later for the slave trade. Diseases such as malaria posed significant challenges due to lack of immunity among Europeans. Fear of African warriors and the difficulty of navigating African rivers also played roles, but the interest in the continent's resources and trade opportunities was evident and persistent over the centuries.
It's important to note that the geography of Africa, including difficult harbors and unnavigable rivers, along with the prevalence of deadly diseases, had made the interior of the continent relatively impenetrable to Europeans before technological advancements in the 19th century. The development of quinine for treating malaria, for example, and the advent of mechanized transportation eventually facilitated European incursions into the African interior, which led to colonization efforts during the so-called "scramble for Africa" in the late 19th and early 20th centuries.