In the context of designing a scalable and cost-effective data processing system on Google Cloud Platform (GCP), you are tasked with selecting the most appropriate service for constructing an ETL (Extract, Transform, Load) pipeline that handles both batch and stream processing. The solution must ensure high fault tolerance, seamless integration with other GCP services, and the ability to automatically scale based on the workload. Considering these requirements, which GCP service should you choose? (Choose one correct option)