The correct answer is: B. A collection of chart data markers.
A data series is a collection of data points that are plotted on a chart. Each data point represents a value, and the data points are connected by lines or curves. The data series is the most important part of a chart, as it represents the data that you are trying to visualize.
A chart legend is a key that explains what each data series in a chart represents. The chart legend is usually located at the bottom of the chart, and it lists the names of the data series and the colors that are used to represent them.
A data label is a text box that displays the value of a data point. Data labels are usually located next to the data points, and they can be used to provide additional information about the data.
I hope this helps! Let me know if you have any other questions.