Which of the following describes Azure Cosmos DB?

Azure Cosmos DB is accurately described as a multi-model NoSQL database management system. This designation highlights its ability to support various data models, including key-value, document, column-family, and graph formats, all within a single database service. This versatility allows developers to choose the data model that best aligns with their application requirements without being constrained to a single database type.

Additionally, Azure Cosmos DB offers globally distributed capabilities, automatic scaling, and low-latency access, making it an ideal solution for applications that require high availability and performance across multiple geographical regions. The multi-model approach is particularly beneficial for modern applications that often need to work with varied data types and structures, aligning perfectly with the demands of dynamic, data-driven environments.

In contrast, relational database management systems are specifically designed for structured data and follow strict schemas, which does not represent Azure Cosmos DB's flexibility. A file storage system for unstructured data would be geared towards storing files rather than providing the database functionalities that include query capabilities and multi-model support. An in-memory data structure store, while fast, does not encompass the broad range of features found in Azure Cosmos DB and is typically limited to specific use cases involving transient data.