Which of the following is a correct way to introduce a source in APA format?

Introducing a source in APA format typically involves mentioning the author's last name and the publication date to provide context for the reader. This method not only gives credit to the original author but also situates the information in its correct temporal context, which is crucial for understanding the relevance and currency of the research.

Using the author's last name followed by the date creates a clear and concise introduction, which is important for academic writing. It informs the reader about the credibility of the source and prepares them for the ideas that follow. This format is also consistent with APA guidelines, which emphasize the importance of author-date citation to substantiate claims throughout the text.

Other options do not follow APA conventions appropriately. For instance, mentioning only the date followed by the author's name does not follow the standard practice and may confuse readers about the origin of the information. Providing the author's full name without a date lacks the timeliness that is often critical in research discourse. Lastly, citing the source in the middle of a sentence can disrupt the flow and clarity, making it difficult for readers to follow the argument being made. Thus, the correct introduction of a source effectively combines authorship and the recency of the work, ensuring adherence to APA standards.