What is at least one limitation for each type of scientific investigation?

In experimental investigations, a key limitation is the potential for controlled conditions to oversimplify complex real-world scenariOS, which may affect the applicability of findings. Observational studies can be limited by the inability to establish causation due to confounding variables. Surveys often suffer from response bias or low response rates, which can skew results. Lastly, case studies may lack generalizability, as they focus on a single instance or a small number of cases, making it difficult to draw broader conclusions.