Answer: Pub/Sub, Bigtable

The correct answer is **C** because **Pub/Sub** is ideal for ingesting data from IoT devices, offering a globally durable message ingestion service that can handle spikes in data volume. **Bigtable** is well-suited for storing time series data, providing low-latency and high-throughput for NoSQL data, making it perfect for scenarios where data needs to be quickly accessible for visualizations and queries. - **Option A** is incorrect because **Dataproc** is not designed for data ingestion in IoT solutions and **Datastore** is not optimized for time series data storage. - **Option B** is incorrect because **Dataproc** is not an ideal service for data ingestion in this context, despite **Bigtable** being suitable for storage. - **Option D** is incorrect because **Datastore** is not the best choice for storing time series IoT data, even though **Pub/Sub** is correct for ingestion. For more details, refer to the [GCP documentation on IoT Overview](https://cloud.google.com/iot/docs/concepts/overview).

Author: LeetQuiz Editorial Team