Which statement describes a functional difference between an internet gateway and a NAT gateway?
Show answer and explanation
Answer: A
An internet gateway is a horizontally scaled VPC component that performs address translation for instances with public or elastic IP addresses, so traffic can flow in both directions. A NAT gateway lets private instances start outbound connections and returns the responses, but it drops unsolicited inbound connections because there is no public address to map them to.
The placement detail is also reversed: the internet gateway attaches to the VPC, while a NAT gateway is deployed in a specific public subnet.
Why the other options are wrong
- B. The two serve different purposes: one provides two-way public connectivity, the other provides outbound-only access.
- C. This reverses the behavior; the internet gateway accepts inbound traffic to public addresses, and the NAT gateway does not.
- D. The attachment points are the other way around: the internet gateway is a VPC-level component and the NAT gateway lives in a subnet.