Which of the following studies qualifies as research with human subjects as per federal regulations?

The selection of the developmental psychologist’s study of toddler interactions is correct because it involves direct observation or interaction with individuals who are identifiable as human subjects. Federal regulations define research involving human subjects as any activity that obtains data through intervention or interaction with individuals or gathers identifiable private information about them. In this case, the study specifically focuses on toddlers, who are considered human subjects since the research engages with them directly regarding their behavior and interactions.

In contrast, the other options do not meet this definition as strictly. A case study on school funding does not involve human subjects directly; rather, it focuses on educational systems and funding strategies. A survey administered to parents involves human subjects, but the nature of the primary research might focus on the perspectives of the parents rather than directly engaging with the behavior of the subjects themselves (the children). Lastly, a literature review on child development is an analysis of existing research rather than a study involving direct interaction or data collection from human subjects, thereby falling outside the scope defined by the federal regulations.