A user has created a VPC with public and private subnets using the VPC wizard. The VPC has
CIDR 20.0.0.0/16. The private subnet uses CIDR 20.0.0.0/24 . The NAT instance ID is i-a12345.
Which of the below mentioned entries are required in the main route table attached with the
private subnet to allow instances to connect with the internet?

A.
Destination: 20.0.0.0/0 and Target: 80

B.
Destination: 20.0.0.0/0 and Target: i-a12345

C.
Destination: 20.0.0.0/24 and Target: i-a12345

D.
Destination: 0.0.0.0/0 and Target: i-a12345

Explanation:
A user can create a subnet with VPC and launch instances inside that subnet. If the user has
created a public private subnet, the instances in the public subnet can receive inbound traffic
directly from the Internet, whereas the instances in the private subnet cannot. If these subnets are
created with Wizard, AWS will create two route tables and attach to the subnets. The main route
table will have the entry “Destination: 0.0.0.0/0 and Target: i-a12345”, which allows all the

instances in the private subnet to connect to the internet using NAT.
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Scenario2.html