Answer:
b) time series
Explanation:
Time-series study: Th term time-series study refers to the process in which it is responsible for analyzing or examine time-series data to get meaningful statistics and related data's characteristics. Time-series study analyzes the future value based on the formerly observed values. It is generally used for longitudinal research that includes a single subject or participants that is being measured continuously and repeatedly in regular intervals of time.
In the question above, the study in which Bonita is participating is best described as a time-series study.