The correct answer is Contoso Stream Analytics.

Contoso Stream Analytics is purpose built for real time processing of high velocity telemetry and for performing immediate analysis with low latency. It runs continuous queries over incoming data streams and supports windowing and pattern matching which makes it suitable for analyzing tracker data as it arrives.

Contoso Stream Analytics also integrates with scalable ingestion services so you can ingest events at high throughput and run analytics jobs on that stream to produce alerts, aggregates, or outputs to dashboards and storage in near real time.

Contoso Data Factory is an orchestration and ETL service that is designed for batch or scheduled data movement and transformation. It is not intended for low latency continuous stream processing or immediate analysis of high velocity telemetry.

Contoso Machine Learning focuses on building, training, and deploying models and it does not provide the continuous stream processing engine needed to ingest and analyze high velocity telemetry on the fly. You could use models with a streaming pipeline, but this service alone is not the real time analytics engine.

Contoso Event Hubs is an event ingestion platform that can receive high velocity streams and serve as the front door for telemetry. It does not perform the analytical processing itself, so it needs to be paired with a stream processing service to achieve immediate analysis.

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