The correct answer is Reduce the maximum number of EC2 instances in the development environments Auto Scaling group.

This approach allows the development environment to scale only as needed within a cost-controlled limit. By reducing the max capacity of the Auto Scaling group, you can ensure that unnecessary instances are not launched during temporary spikes or misconfigurations. Since the dev environment has predictable and low usage, this provides sufficient resources without waste.

Reconfigure the target group in the development environment to have only one EC2 instance as a target removes redundancy. While cheaper, this creates a single point of failure, which violates best practices even for non-production environments. High availability is still a consideration for development, especially for testing failover or deployment scenarios.

Change the ALB balancing algorithm to least outstanding requests is related to performance optimization under load, but it has no direct effect on cost savings. This option doesnt limit EC2 usage or change scaling behavior.

Reduce the size of the EC2 instances in both environments might save money but doesnt specifically address the dev environment. Downsizing production instances could negatively impact performance during peak traffic, which the scenario says must be handled effectively.

Why this question matters: It tests your ability to apply Auto Scaling best practices in a multi-environment setup and identify cost-optimization strategies tailored to different usage profiles. Recognizing when and where to tune capacity settings is crucial in cloud cost management.

Tip: In questions where environments have different performance profiles, focus your optimization strategy on the environment with lower demand, and look for Auto Scaling configuration options like min, max, and desired capacity.

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