Final answer:
The observation method of collecting primary data involves directly observing and recording behaviors or events.
Step-by-step explanation:
The observation method of collecting primary data involves directly observing and recording behaviors or events. From the given options, option b. Recording the amount of time a shopper stops in front of a point-of-purchase display is an example of the observation method. By observing and recording how long shoppers stop at a display, data can be collected to analyze shopper behavior and preferences.