Answer – A and C
The AWS documentation mentions the following
A virtual private gateway is the VPN concentrator on the Amazon side of the VPN connection. You create a virtual private gateway and attach it to the VPC from which you want to create the VPN connection.
A customer gateway is a physical device or software application on your side of the VPN connection.
For more information on AWS VPN please refer to the below URL:
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_VPN.html