Answer: b. Cross-sectional study
Step-by-step explanation:
A. Correlational study is a research design in which a researcher seeks to find out if two or more variables are related and if so, then in what way. An example is difference in people's height,
B. Cross-sectional study is a type of study that involves observing a population or representative subset at a particular point in time and analysing the data. An example is evaluating people from different ages.
C. Archival study involves seeking out and retrieving evidence from archival records.
D. Longitudinal study involves gathering data from observing the same individuals repeatedly over a period of time.