Dr. Sanjay collects data on how often strangers approach one another at the park on weekend afternoons. One strength of this observational approach is that it:

Occurs in a real-world setting.

Explanation:

When a researcher questions something that requires observation of an animal in the real world it is important that nothing happens that may change the behavior of the animal that is being observed. This affects the quality of the research as it is influenced by outside factors.

Here, Dr. Sanjay is observing how often strangers approach one another at the park on weekend afternoons. People are interacting the way they would if he was not present. This makes the observation in the real-world setting valid.