A company is running an order processing system on Amazon EC2 instances.

 The combination of AWS services that the application can use to migrate to a microservices-based application are Amazon Simple Queue Service (Amazon SQS) and AWS Lambda. Amazon SQS is a fully managed message queuing service that enables customers to decouple and scale microservices, distributed systems, and serverless applications. The application can use Amazon SQS to send, store, and receive messages between the microservices, ensuring that each message is processed only once and in the right order. AWS Lambda is a serverless compute service that allows customers to run code without provisioning or managing servers. The application can use AWS Lambda to create and deploy microservices as functions that are triggered by events, such as messages from Amazon SQS. AWS Migration Hub, AWS AppSync, and AWS Application Migration Service are not the best services to use for migrating to a microservices-based application. AWS Migration Hub is a service that provides a single location to track the progress of application migrations across multiple AWS and partner solutions. AWS AppSync is a service that simplifies the development of GraphQL APIs for real-time and offline data synchronization. AWS Application Migration Service is a service that enables customers to migrate their on-premises applications to AWS without making any changes to the applications, servers, or databases.