A Solutions Architect is tasked with securing a web application environment hosted in a private subnet on Amazon EC2 instances. These instances serve sensitive content and are placed behind a load distribution service offered by AWS. How can the Architect regulate the incoming network flow to guarantee that the web servers exclusively accept browser traffic that is encrypted?
Install a software-based firewall on each EC2 instance to reject requests arriving on any port other than 443.
Modify the security group rules associated with the EC2 instances to allow ingress only on port 443, ensuring that the load distribution service listens for and passes through traffic on the same port.
Apply stringent rules on the Network ACLs for the associated subnets allowing traffic only on port 443, while keeping the existing security group rules unchanged.
Configure the load distribution service to listen only on port 443 but do not change the rules for the security group attached to the EC2 instances.