Amazon Aurora is the correct choice because it is a fully managed relational database that preserves MySQL compatibility while offering higher performance and managed high availability.

Amazon Aurora commonly outperforms standard MySQL and accepts MySQL clients and tools so applications usually need minimal changes. It provides automated backups, read replicas, and multi availability zone durability which meet the need for managed high availability and reduced operational overhead.

Amazon Neptune is a purpose built graph database and it is not intended for relational or MySQL compatible workloads so it would not be a suitable replacement.

Amazon DynamoDB is a NoSQL key value and document database and migrating to it would require rearchitecting relational schemas and SQL queries so it does not fit when MySQL compatibility is required.

Amazon ElastiCache provides in memory caching to complement databases and it does not serve as persistent relational primary storage so it cannot replace a MySQL database for primary data storage.

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