Correct answer:
Import the SSL certificate into AWS Certificate Manager (ACM). Configure an Application Load Balancer with an HTTPS listener that uses the ACM certificate to handle SSL termination.

Explanation:
This is the most effective and scalable solution. By offloading SSL termination to an Application Load Balancer (ALB), the EC2 instances no longer need to perform compute-intensive encryption and decryption tasks. The ALB handles incoming HTTPS traffic, terminates SSL at the edge using the ACM certificate, and forwards decrypted HTTP traffic to the backend EC2 instances. This improves performance, supports auto scaling, and simplifies certificate management.

Why the other options are incorrect:

Uploading the SSL certificate to an Amazon S3 bucket does not provide any SSL termination capabilities. S3 cannot be used as a secure endpoint to offload SSL decryption for dynamic web applications running on EC2.
Adding a third EC2 instance as a reverse proxy with the SSL certificate would offload SSL from the primary instances, but it introduces more operational complexity. You must manage and monitor another EC2 instance, configure traffic routing, and ensure high availability manuallythis increases overhead instead of reducing it.
Generating a new certificate with AWS Certificate Manager and installing it on the EC2 instances does not address the core issue. Even if the certificate is newer or easier to manage, SSL processing would still happen on each EC2 instance, consuming the same amount of CPU resources and failing to improve performance.

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