Which solution maintains the Salesforce user interface while allowing CRUD operations on an external data warehouse?

The correct choice is based on the need to maintain the Salesforce user interface while performing CRUD operations on an external data warehouse. Lightning Connect is specifically designed to facilitate real-time integration with external data sources without disrupting the native Salesforce experience.

By using Lightning Connect alongside a custom Apex Adapter, organizations can seamlessly integrate external data into their Salesforce environment. This approach allows users to interact with external data as if it were native to Salesforce, enabling efficient CRUD operations while preserving the integrity of the user interface. The custom Apex Adapter serves as the middleware, handling the data transformations and communication between Salesforce and the external data warehouse, ensuring that users can manipulate data without needing to leave the Salesforce platform.

Other options may involve rendering data or utilizing different methods of integration that could either complicate the user interface experience or not fully support real-time operations on external data. Therefore, Lightning Connect with a custom Apex Adapter stands out as the most effective solution for this scenario.