Answer: Databricks web application

In the classic Databricks architecture, the control plane includes management services that handle workspace management, job scheduling, and user interface components. The Databricks web application is part of the control plane, providing the user interface for managing workspaces, clusters, jobs, and notebooks. **Key points:** - **Worker node (A)**: Part of the data plane, runs in customer's cloud account - **JDBC data source (B)**: External data source, not part of Databricks architecture - **Databricks web application (C)**: ✓ Correct - hosted in control plane - **Databricks Filesystem (D)**: Part of the data plane, runs in customer's cloud storage - **Driver node (E)**: Part of the data plane, runs in customer's cloud account The control plane manages administrative functions while the data plane handles actual data processing in the customer's cloud environment.

Author: Keng Suppaseth