A researcher interested in a relationship between amount of

A researcher interested in a relationship between amount of sleep and stress recorded a typical number of sleep hours per night and current stress level of each participant of the study. This study is an example of _____________.

A. an experiment
B. noneequivalent groups study
C. pre-post test study
D. correlational study
E. none of the above

Solution

D. Correlational study

as it is trying to establish a relationship between two variables, amount of sleep and stress level.