What should the solutions architect recommend?
Launch an Amazon EC2 instance in us-east-1 and migrate the site to it.
Move the website to Amazon S3. Use cross-Region replication between Regions.
Use Amazon CloudFront with a custom origin pointing to the on-premises servers.
Use an Amazon Route 53 geo-proximity routing policy pointing to on-premises servers.
Explanations:
Launching an EC2 instance in us-east-1 does not address latency for European users since the backend would still be in the U.S., leading to suboptimal loading times.
Moving the website to Amazon S3 and using cross-Region replication would not provide immediate improvements for European users as it requires the site to be fully migrated to S3 and set up correctly, which is not feasible in a short time frame.
Using Amazon CloudFront with a custom origin allows caching of content closer to European users, reducing latency while keeping the backend in the U.S. This solution can be deployed quickly and efficiently.
Amazon Route 53 geo-proximity routing can help direct traffic, but it does not provide the performance benefits of caching and CDN capabilities that CloudFront offers. It would not significantly improve loading times for European users.
I guess:
Use Amazon CloudFront with a custom origin pointing to the on-premises servers.