Answer:
Cohort design longitudinal design.
Explanation:
A longitudinal study is the study of repeated observation of the same variables over a long or short period. It is an observational study and can be structured as longitudinal with randomized experiments. These studies are used in social and clinical psychology to measure or observe the fluctuation in emotions, behavior, in day to day life. In the development study, it has been used to know the developmental trends across life. In social psychology, it has been used to measure life events, throughout the life span. Theses study allow the scientist to differentiate between short term study to long term study such as poverty. The longitudinal study observes the same people over the year. These studies observe the state or world without manipulation.