Which scenario is an example of a longitudinal research design?
a. dr. michaels administers a questionnaire to gather data on childhood friendships to a group of 5-year-olds. she meets with the original group of children in the study every year and gives them the same questionnaire until they are 10 years old.
b. dr. michaels administers a questionnaire to gather data on childhood friendships to a group of 7-year-olds.
c. dr. michaels administers a questionnaire to gather data on childhood friendships to a group of 5-, 6-, and 7-year-olds. she meets with all three groups and gives them the same questionnaire for the next 3 years and stops when they are 8, 9, and 10 years old.
d. dr. michaels administers a questionnaire to gather data on childhood friendships to a group of 7-year-olds and a group of 10-year-olds.