Which AWS service will meet these requirements?

Explanations:

Amazon DynamoDB is a fully managed, serverless key-value and document NoSQL database that automatically scales and manages data replication across multiple regions. It is designed for high availability and performance, making it the ideal choice for applications requiring fast and consistent performance.

Amazon RDS (Relational Database Service) is a managed relational database service, not a NoSQL database. It supports SQL databases like MySQL, PostgreSQL, and Oracle but does not offer the serverless and key-value model features required.

Amazon Aurora is a relational database that is part of RDS. While it is fully managed and can scale, it is not a NoSQL database and does not support the key-value data model.

Amazon MemoryDB for Redis is a fully managed, Redis-compatible in-memory database service, but it primarily supports data structures like strings, hashes, and lists. It is not a key-value NoSQL database and is not serverless in the same sense as DynamoDB.