You are a cloud architect for a real-time financial analytics firm. The application needs to make real-time decisions based on data from various sources. The data is critical and must be encrypted at rest and in transit. Which GCP service is most appropriate for this use case?

*Explanation:* For a real-time financial analytics application that requires real-time decision-making based on encrypted data, the most suitable GCP service is **Cloud Bigtable (option C. **. Cloud Bigtable is designed for high-throughput, low-latency data access and supports encryption at rest and in transit. It is well-suited for storing and retrieving critical financial data in real-time. The other options are not specifically tailored for real-time analytics and may not provide the same level of performance and security.