Which of these are reasonable solutions for allowing Internet users to connect to an ECS instance without a public IP?

Assigning a public IP address to the ECS instance at creation is a reasonable solution for enabling Internet users to connect to the instance. When an ECS instance has a public IP address, it becomes directly accessible from the Internet, allowing users to connect without needing any additional configurations.

While binding an Elastic IP (EIP) to the ECS instance is a method for providing a stable public IP that can be reassigned if the instance is stopped and started, it is not about the instance being created without a public IP. This means it doesn't fit the context of the question as well as assigning a public IP during creation.

Attaching a NAT Gateway with DNAT rules is a strategy that can allow Internet users to reach private instances by translating the address, but it typically involves having public-facing assets (either via EIP or public IP) in your VPC architecture.

Creating a VPN connection, on the other hand, allows for secure access but requires specific client-side configurations and does not inherently provide a direct way for general Internet users to connect, particularly those not part of the VPN.

Thus, the most straightforward and effective method from the options provided for allowing Internet users to connect directly to the ECS instance is to assign a public IP address when creating the