Default CIDR Range for AWS Default VPC Setup

Answer - B.

This is mentioned in the AWS documentation.

Default VPCs are assigned a CIDR range of 172.31.0.0/16

Default subnets within a default VPC are assigned /20 netblocks within the VPC CIDR range.

For more information on VPC's, please refer to the below link:

The correct answer is B. 172.31.0.0/16

When you create a new AWS account, a default Virtual Private Cloud (VPC) is created in each AWS region. This VPC is automatically created by AWS and is designed to make it easy for you to get started with AWS by providing a default network infrastructure.

The default VPC is created with a /16 CIDR block, which provides 65,536 private IP addresses. The default CIDR block used for the default VPC in AWS is 172.31.0.0/16.

This default CIDR block is divided into smaller subnets, with the first subnet being 172.31.0.0/20. Each subnet has a block of IP addresses that are available for use by your instances.

It's important to note that the default VPC is not the same as a custom VPC that you can create. With a custom VPC, you have full control over the network architecture, including the IP address range and the configuration of subnets and routing tables.

In summary, the default CIDR range provided for the default VPC's setup in AWS is 172.31.0.0/16, which is divided into smaller subnets with the first subnet being 172.31.0.0/20.