The correct selection is B. An unmanaged package is appropriate for a one-time transfer of an existing application into another org when the receiving organization needs to own and customize the components. Building a managed-product lifecycle or recreating the application from scratch would add unnecessary time and complexity. From a deployment perspective, the same release should be reproducible across environments, with dependencies, metadata/data differences, API behavior, and target-org constraints identified before production. Automation is valuable because it turns deployment knowledge into a controlled process rather than relying on memory or manual reconstruction. The rejected alternatives do not meet the deployment requirement because they introduce drift, ignore target-org compatibility, or substitute a convenience tool for a reproducible release artifact. For this scenario, the decisive point is therefore the platform behavior represented by the selected option (B. Create an unmanaged package of the app and deploy in NTO's org.). Applying that rule consistently keeps the implementation aligned with Salesforce-supported lifecycle practices and makes the resulting change easier to review, validate, and operate across environments.

Study Guide reference: Deploying --- Metadata API and Tooling API; deployment validation; package/change-set deployment; data migration; dependency management.