There is a requirement to split a VPC with a CIDR block of 10.0.0.0/24 into two subnets, each of which should give 128 IP addresses (including the 5 fixed IPs reserved by AWS). Can this be done and if so, how will the allocation of the IP addresses be configured? Choose the correct answer from the below options.

Answer options:

A.One subnet will use CIDR block 10.0.0.0/127 (for addresses 10.0.0.0 - 10.0.0.127) and the other will use CIDR block 10.0.0.128/255 (for addresses 10.0.0.128 - 10.0.0.255).
B.One subnet will use CIDR block 10.0.0.0/25 (for addresses 10.0.0.0 - 10.0.0.127) and the other will use CIDR block 10.0.1.0/25 (for addresses 10.0.1.0 - 10.0.1.127).
C.One subnet will use CIDR block 10.0.0.0/25 (for addresses 10.0.0.0 - 10.0.0.127) and the other will use CIDR block 10.0.0.128/25 (for addresses 10.0.0.128 - 10.0.0.255).
D.This is not possible.

Answer – C
This is clearly given in the AWS documentation.
" For example, if you create a VPC with CIDR block 10.0.0.0/24, it supports 256 IP addresses. You can break this CIDR block into two subnets, each supporting 128 IP addresses. One subnet uses CIDR block 10.0.0.0/25 (for addresses 10.0.0.0 - 10.0.0.127) and the other uses CIDR block 10.0.0.128/25 (for addresses 10.0.0.128 - 10.0.0.255)".
For more information on VPC and subnets, please see the below link-
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Subnets.html
To get the IP addresses and subnets, please see the below link-
http://www.subnet-calculator.com/cidr.php