Based on the information provided, it is not clear where the "Selected Coordinates" option is located on the PowerPoint ribbon. However, to change the values in a graph in PowerPoint, you would typically click on the chart and then navigate to the "Chart Tools" section on the ribbon. Within the "Chart Tools" section, you will find options to edit and modify the chart data, such as "Edit Data" or "Select Data". The exact location may vary depending on the version of PowerPoint you are using.
