You want to automate the creation of a peering connection between VPCs in your AWS account. How would you achieve this?

Answer options:

A.Use a Cloudformation template to deploy and peer the VPCs.
B.Use an Opswork stack to peer the VPCs.
C.Use Cloudtrail along with a Lambda function.
D.Use Cloudwatch metrics along with a Lambda function.

Answer – A
An example of this is given in the AWS Documentation.
AWS::EC2::VPCPeeringConnection
A VPC peering connection enables a network connection between two virtual private clouds (VPCs) so that you can route traffic between them using a private IP address. For more information about VPC peering and its limitations, see VPC Peering Overview in the Amazon VPC Peering Guide.
Note
You can create a peering connection with another AWS account. For a detailed walkthrough, see Walkthrough: Peer with an Amazon VPC in Another AWS Account.
Topics
Syntax
Properties
Return Values
Examples
Syntax
To declare this entity in your AWS CloudFormation template, use the following syntax:
JSON
Option B is incorrect since Cloudformation should be used instead of Opsworks.
Options C and D are incorrect since these would not assist in the automatic creation of resources.
For more information on VPC peering with Cloudformation, please refer to the below URL
https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-ec2-vpcpeeringconnection.html