Martinez Is Interested in How Thinking Changes in Adolescence and Early

Multiple Choice

Martinez is interested in how thinking changes in adolescence and early adulthood. She identifies two hundred 18-year-olds and has them respond to a written set of questions. She then waits four years, contacts them all again, and has them respond to a similar set of questions. Finally, she waits another four years, contacts the people again (who are now 26 years old) , and asks them one last time to respond to her questions. The study Dr. Martinez has conducted is best considered an example of:

A) a longitudinal study
B) a cross-sectional study
C) a sequential-cohort study
D) an age-cohort experiment