What will happen in this scenario?

A user has created a VPC with CIDR 20.0.0.0/16. The user has created one subnet with CIDR 20.0.0.0/16 in this VPC. The user is trying to create another subnet with the same VPC for CIDR 20.0.0.1/24.

What will happen in this scenario?
A . The VPC will modify the first subnet CIDR automatically to allow the second subnet IP range
B . It is not possible to create a subnet with the same CIDR as VPC
C . The second subnet will be created
D . It will throw a CIDR overlaps error

Answer: D

Explanation:

A Virtual Private Cloud (VPC) is a virtual network dedicated to the user’s AWS account. A user can create a subnet with VPC and launch instances inside that subnet. The user can create a subnet with the same size of VPC.

However, he cannot create any other subnet since the CIDR of the second subnet will conflict with the first subnet.