The two most common primary research methods in the social sciences are

A) not appropriate for test marketing.
B) experiments and observations.
C) surveys and interviews.
D) test panels.

Surveys and interviews are the two most common primary research methods in the social sciences because they allow researchers to collect data directly from individuals and can provide in-depth information on attitudes, beliefs, behaviors, and opinions. While experiments and observations can also be used in social science research, they may not be appropriate or feasible for all research questions. Test panels may be used in marketing research, but they are not as commonly used in the broader field of social science research.