The best answer is: Refactor the EC2-based script into an AWS Lambda function using the appropriate language runtime.

Replacing the polling script on the EC2 instance with an AWS Lambda function is the most cost-effective and scalable approach. Lambda allows you to run code without provisioning or managing servers. It can be invoked automatically in response to SQS messages, enabling an event-driven, serverless architecture. Lambda scales automatically with the volume of messages, so as the queue grows, multiple Lambda invocations can run in parallel to process messages concurrentlyresulting in lower latency and better resource utilization.

The option Resize the EC2 instance to a larger type to improve processing performance increases cost and does not address scalability effectively. Even a larger EC2 instance is limited in how many messages it can process concurrently and requires ongoing management, patching, and monitoring.

The option Use Amazon EventBridge to stop the EC2 instance when usage is low introduces complexity and latency. While it may help reduce cost during idle periods, it does not provide the same elasticity as Lambda and may delay message processing during instance startup.

The option Use AWS Systems Manager Run Command to manually trigger the script execution as needed is not suitable for a continuously running, event-driven workload. It introduces manual overhead and does not offer the automation and scalability required for processing a high volume of SQS messages.

This question is important because it tests your ability to modernize workloads and choose serverless services for improved scalability and cost-efficiency. When the requirements mention growing traffic and minimizing operational management, AWS Lambda is often the right directionespecially for SQS-triggered processing.

The tricky part here is recognizing that increasing instance size or scripting automation with EC2 is reactive and doesn't align with modern, elastic, event-driven architecture patterns that AWS encourages.

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