What function does the height of the bars in a Histogram serve?

The height of the bars in a histogram is crucial as it represents the size of each group or interval within the data set. Each bar stands for a specific range of values, known as a bin, and the height corresponds to the frequency of data points that fall within that range. This visualization allows for a clear understanding of the distribution of data, showcasing how many observations exist in each specified range.

While other options mention concepts related to the analysis of data, they do not accurately reflect the specific role of the heights of the bars in a histogram. For instance, indicating the average of the data would require a different statistical measure, and showing the timeline would typically involve a time series plot rather than a histogram, which focuses on frequency. Similarly, while highlighting the most common data points might suggest a mode, a histogram's primary function revolves around demonstrating the frequency of occurrences across intervals rather than pinpointing exact values.