What feature should a developer use to allow manual changes to the service URL in the sandbox?

The correct answer involves utilizing the service credential URL field to enable manual changes to the service URL in the sandbox environment. This field is designed specifically for managing service credentials, such as endpoints, allowing developers to override default settings in scenarios like testing or staging where specific adjustments are necessary.

This approach is beneficial during development and testing in a sandbox, as it provides flexibility and control over configurations that may need to change frequently depending on the testing requirements or service modifications.

On the other hand, site preferences and global preferences generally serve different purposes; they are not specifically tailored to manage service URLs in the same way that the service credential URL field is. The service status and its associated settings may not offer the same level of specificity and direct access to URL manipulation required for effective sandbox management. This makes the service credential URL field the most appropriate tool for this task.