To Study the Effects of Age on Adult Memory, an Investigator

Multiple Choice

To study the effects of age on adult memory, an investigator administers a memory test to a group of college students and then as soon as possible administers the same test to those students' parents and grandparents. The design of this study is best described as

A) case-study.
B) double-blind.
C) longitudinal.
D) cross-sectional.