Identify the sampling method that was used.
All residents in one building of an apartment complex are asked to complete a survey.
Random
Stratified

In this scenario, a sampling method is used where all residents from a specific group—namely, one building in an apartment complex—are surveyed. This is not random sampling because it’s not selecting individuals randomly from the entire population of the apartment complex. Instead, it represents a whole segment or cluster, which makes it more akin to a “cluster sampling” method.

If your goal is a representation of opinions from the wider apartment community, consider selecting a random sample that includes residents from multiple buildings. This way, it ensures a more inclusive perspective and helps avoid bias towards the specific building’s demographic, leading to more reliable survey results.