Which step should the solutions architect take to resolve this issue?
Update the subnet route table with a route to the interface endpoint
Enable the private DNS option on the VPC attributes
Configure the security group on the interface endpoint to allow connectivity to the AWS services
Configure an Amazon Route 53 private hosted zone with a conditional forwarder for the internal application
Explanations:
Updating the subnet route table is not necessary for interface endpoints as they are designed to be accessible from within the VPC without modifying route tables.
Enabling the private DNS option allows the service names to resolve to private IP addresses instead of public IPs, facilitating internal connectivity to the interface endpoints.
While configuring the security group is important for allowing traffic, the primary issue here is the DNS resolution to public IPs, not security group rules.
Configuring a Route 53 private hosted zone with a conditional forwarder would not directly resolve the issue of public IP address resolution for AWS services accessed via interface endpoints.
I evaluate that the answer is:
Enable the private DNS option on the VPC attributes