What is the primary purpose of the 'Source' step settings in Query Editor?

The primary purpose of the 'Source' step settings in Query Editor is to modify the connection to the data source. This step is crucial because it defines where your data is coming from and allows you to adjust the connection settings if necessary. For instance, if the location of the data source changes or if there are changes to the credentials needed to access the data, the 'Source' settings provide a way to update these details without needing to recreate the entire query.

By modifying the connection, you ensure that the data you are working with in Power BI is accurately reflecting the current data source. This is essential for maintaining data integrity and ensuring that your reports and dashboards are based on the most recent and relevant data.

The other options represent actions that are important but do not encapsulate the primary purpose of the 'Source' step settings. Loading data is a function that happens after the connection is established, deleting a connection pertains to managing data connections rather than modifying them, and refreshing a dataset refers to updating the data in Power BI with any new data from the data source, which is a separate process from establishing the initial connection in the Query Editor.