Which of the following can be used to ensure that resources from the internet cannot initiate an IPv6 connection to instances in your public subnet

Answer options:

A.Internet gateway
B. egress-only Internet gateway
C.ingress-only Internet gateway
D.NAT gateway

Answer - B
The AWS documentation mentions the following on egress-only Internet gateway
An egress-only Internet gateway is a horizontally scaled, redundant, and highly available VPC component that allows outbound communication over IPv6 from instances in your VPC to the Internet, and prevents the Internet from initiating an IPv6 connection with your instances.
For more information on egress-only Internet gateway, please visit the below URL:
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/egress-only-internet-gateway.html