What research method would be most appropriate for a study of cultural changes over long periods of time?

A) Participant observation, in which individuals from different age groups are observed
B) A survey, in which people are asked about their own behavior and attitudes over a period of time
C) Content analysis, in which media from different time periods are sampled
D) Experiment, in which people are asked to act like individuals from certain eras would have acted

Content analysis would be the most appropriate research method for studying cultural changes over long periods of time because it involves analyzing media from different time periods. This would provide a way to track changes in cultural norms, values, and beliefs over time. Participant observation and experiments would not be feasible for studying long-term changes, as they are typically conducted over shorter time frames. Surveys may be useful for studying individual attitudes and behaviors, but they may not provide a comprehensive picture of larger cultural trends.