Researchers Observe the Number of People Who Go to a Bar

Multiple Choice

Researchers observe the number of people who go to a bar alone on the days before and after Valentine's Day. They find that the number of people increases leading up to Valentine's Day, drops significantly on Valentine's Day, and then rises quickly back up again on the day afterwards. This is best conceptualized as an example of:

A) pilot research.
B) experimental research.
C) longitudinal research.
D) field research.