Which of the following is NOT a source of scholarly articles and professional research?

Wikipedia is not considered a source of scholarly articles and professional research because it is a user-generated platform that allows anyone to contribute and edit content. The reliability and credibility of the information can vary significantly, as it does not undergo the rigorous peer-review process that characterizes scholarly sources. In contrast, the other options listed—LexisNexis, DOAJ, and InfoTrac—are reputable databases that provide access to peer-reviewed journals, articles, and professional research materials. These platforms are specifically designed to host verified and authoritative content, making them suitable for academic and professional research.