You want your report readers to be able to view your bar chart visual for any year that they choose. What tool could you use?

Using a slicer is the best choice for allowing report readers to interactively choose which year they want to view in a bar chart visual. Slicers act as a visual filter in reports, enabling users to select specific criteria that instantly update the displayed data. This interactivity enhances user experience by letting them focus on the information that matters most to them, such as comparing data across different years.

In this scenario, when a slicer is applied to a report, users can easily select a year from a list, which adjusts the bar chart to reflect data for that specific year. This capability facilitates a more dynamic analysis, as users can explore trends or changes in the data over time.

Other options, like conditional formatting, would primarily affect the visual representation of data rather than allow for dynamic filtering. A treemap provides a different visualization type suitable for displaying hierarchical data rather than focusing on temporal filtering. Z-order pertains to the stacking order of objects in the report and does not relate to user-interactive filtering of data. Thus, the slicer is the most effective tool for this purpose.