Answer:
A. He believed that Livingstone's work was important.
Step-by-step explanation:
Henry Stanley, formerly named John Rowlands, was a Welsh-American journalist, explorer, and soldier, among others who helped seek out David Livingstone and bring him back. Moreover, Stanley was known for continuing Livingstone's work even after the man's death.
David Livingstone was a missionary as well as a pioneer who had gone to Africa to find the source of the river. Stanley had arrived in Africa bringing resources and supplies to Livingstone and was also a pallbearer at the missionary's death in 1873. He later continued Livingstone's work, choosing to stay in Africa and continuing the search for the Nile's source because he believed in the importance of the man's work.
Thus, the correct answer is option A.