An Enterprise Company Wants to Implement Cost Controls for All

An enterprise company wants to implement cost controls for all its accounts in AWS Organizations, which has full features enabled. The company has mapped organizational units (OUs) to its business units, and it wants to bill these business units for their individual AWS spending. There has been a recent spike in the company's AWS bill, which is generating attention from the Finance team. A Solutions Architect needs to investigate the cause of the spike while designing a solution that will track AWS costs in Organizations and generate a notification to the required teams if costs from a business unit exceed a specific monetary threshold. Which solution will meet these requirements?

A) Use Cost Explorer to troubleshoot the reason for the additional costs. Set up an AWS Lambda function to monitor the company's AWS bill by each AWS account in an OU. Store the threshold amount set by the Finance team in the AWS Systems Manager Parameter Store. Write the custom rules in the Lambda function to verify any hidden costs for the AWS accounts. Trigger a notification from the Lambda function to an Amazon SNS topic when a budget threshold is breached.
B) Use AWS Trusted Advisor to troubleshoot the reason for the additional costs. Set up an AWS Lambda function to monitor the company's AWS bill by each AWS account in an OU. Store the threshold amount set by the Finance team in the AWS Systems Manager Parameter Store. Write custom rules in the Lambda function to verify any hidden costs for the AWS accounts. Trigger an email to the required teams from the Lambda function using Amazon SNS when a budget threshold is breached.
C) Use Cost Explorer to troubleshoot the reason for the additional costs. Create a budget using AWS Budgets with the monetary amount set by the Finance team for each OU by grouping the linked accounts. Configure an Amazon SNS notification to the required teams in the budget.
D) Use AWS Trusted Advisor to troubleshoot the reason for the additional costs. Create a budget using AWS Budgets with the monetary amount set by the Finance team for each OU by grouping the linked accounts. Add the Amazon EC2 instance types to be used in the company as a budget filter. Configure an Amazon SNS topic with a subscription for the Finance team email address to receive budget notifications.