Which of the following describes the count of occurrences of a behavior within a given period?

The correct choice is frequency, as it specifically refers to the number of times a particular behavior occurs within a designated period. This term is essential in behavior analysis as it provides clear data on how often a behavior manifests, allowing for better assessment and intervention planning. Frequency is often represented simply as a count of occurrences, which makes it a straightforward and useful metric for practitioners.

Rate, while related, refers to frequency expressed in relation to time, essentially combining both the count of occurrences and the duration of observation. Interval pertains to the timing or length over which data is collected and does not quantify behavior by count. Count interval is not a commonly used term in behavior analysis and may create confusion as it does not align with standard definitions or applications. Thus, frequency is the most accurate term pertaining to the count of occurrences of behavior over a specified time frame.