Which example best illustrates using the internet as a research tool in human subjects research?

Using the internet as a research tool in human subjects research is effectively illustrated by the scenario where an investigator posts a URL link to a survey on their social media profile. This approach leverages online platforms to reach potential participants directly and easily. By sharing a survey link in a widely accessible environment, the researcher can gather responses from a diverse pool of participants, which enhances the representativeness of the sample and facilitates data collection in a manner that is both cost-effective and efficient.

This method is particularly relevant in social and behavioral research, where reaching specific populations can be challenging. Furthermore, it exemplifies the use of the internet to facilitate direct engagement with participants, making it a powerful tool for collecting data in a secure and ethical manner.

In contrast, the other options lack the effective combination of the internet as a research tool specifically focused on human subjects. Collecting personal emails for follow-up research does not utilize the internet effectively as a research tool in the context of human subjects engagement. Reviewing online articles, while useful for background research, does not involve direct interaction with human subjects. Similarly, analyzing social media comments can provide insights, but this method does not offer the same level of structured interactive engagement with participants as the survey does.