Which solution will meet these requirements with the LEAST effort?
Create a tag policy that contains the allowed project tag values in the organization’s management account. Create an SCP that denies the cloudformation:CreateStack API operation unless a project tag is added. Attach the SCP to each OU.
Create a tag policy that contains the allowed project tag values in each OU. Create an SCP that denies the cloudformation:CreateStack API operation unless a project tag is added. Attach the SCP to each OU.
Create a tag policy that contains the allowed project tag values in the AWS management account. Create an IAM policy that denies the cloudformation:CreateStack API operation unless a project tag is added. Assign the policy to each user.
Use AWS Service Catalog to manage the CloudFormation stacks as products. Use a TagOptions library to control project tag values. Share the portfolio with all OUs that are in the organization.