On the topic of planet Earth…a university planetary science professor or a NASA astrophysicist would be considered reliable sources. Even professionals can have uncommon views, though, so do some research. Have the sources published peer-reviewed data on the subject? There are a few folks with impressive-sounding degrees and titles who claim that aliens visiting Earth constructed the pyramids, but an overwhelming majority of scientists, engineers, and historians disagree with them. The author's purpose for writing this passage was to .

A. argue that research is not always effective in weeding out unreliable sources
B. highlight the ways in which reliable sources can be used to debunk most conspiracy theories
C. emphasize the importance of researching sources to determine their reliability
D. suggest that reliable sources seek to inform readers about the dangers of conspiracy theories