An example of structured observation from the options provided would be:
After receiving an anonymous tip, a supervisor observes his staff to see if any of them are downloading music while they should be working.
Structured observation involves a systematic method of observing specific behaviors or events in a controlled manner, often seeking to measure certain outcomes or variables. In this case, the supervisor has a specific focus on a particular behavior (downloading music) during a defined context (the work environment), which aligns with the principles of structured observation.