Final answer:
The correct answer is option d) Advancement of Christianity and civilization in Africa.
Step-by-step explanation:
David Livingstone believed that opening the interior of Africa to Christianity and trade would lead to the advancement of Christianity and civilization in Africa. Livingstone was convinced that through the establishment of trade routes and the spread of Christian teachings, there would be an improvement in moral standards as well as an end to the slave trade, thus elevating the quality of life for African peoples.
His motivations were intertwined with the broader imperialistic ambitions of the 19th century, where European nations were engaged in the colonization of other parts of the world, including Africa, often under the guise of a civilizing mission.