How must changes made to a data source item be made visible on the website after an item is published?

The correct approach to making changes to a data source item visible on the website involves publishing the data source item itself. In Sitecore, when you modify a data source item, those changes will not be reflected on the live site until the item is published. This is because Sitecore utilizes a publishing mechanism to manage content visibility and ensure that only approved and relevant data is displayed to end-users.

If the data source item is not published after modifications, the website will continue to display the previous version of that item, preventing any updates from being seen by visitors. Once the data source item is published, it will be updated in the relevant areas of the site where it is used, allowing the changes to take effect immediately for users viewing the site.

Other options refer to actions that do not directly address the visibility of changes to a specific data source item. While republishing the main item might seem like a logical approach, it does not address the need to publish individual data source items, which are crucial for ensuring that content reflects the most recent edits. The notion that the data source item does not need to be published or that approval is necessary is also misleading in the context of standard publishing practices within Sitecore.