To prevent changes to existing line items of the sap.test::myTable table, you can use the OData service that specifies the update authorization as no-authorization for the table. This means that the OData service does not allow any update operations on the table, such as PUT, PATCH, or MERGE. The option A shows the code snippet that defines the OData service with this restriction. The other options do not have the update no-authorization clause for the table, and therefore, they do not prevent changes to the existing line items. References: OData Service Authorization, OData Security Considerations.