Your Company Has Multiple Applications Running on AWS

Your company has multiple applications running on AWS. Your company wants to develop a tool that notifies on-call teams immediately via email when an alarm is triggered in your environment. You have multiple on-call teams that work different shifts, and the tool should handle notifying the correct teams at the correct times. How should you implement this solution?

A) Create an Amazon SNS topic and an Amazon SQS queue. Configure the Amazon SQS queue as a subscriber to the Amazon SNS topic. Configure CloudWatch alarms to notify this topic when an alarm is triggered. Create an Amazon EC2 Auto Scaling group with both minimum and desired Instances configured to 0. Worker nodes in this group spawn when messages are added to the queue. Workers then use Amazon Simple Email Service to send messages to your on call teams.
B) Create an Amazon SNS topic and configure your on-call team email addresses as subscribers. Use the AWS SDK tools to integrate your application with Amazon SNS and send messages to this new topic. Notifications will be sent to on-call users when a CloudWatch alarm is triggered.
C) Create an Amazon SNS topic and configure your on-call team email addresses as subscribers. Create a secondary Amazon SNS topic for alarms and configure your CloudWatch alarms to notify this topic when triggered. Create an HTTP subscriber to this topic that notifies your application via HTTP POST when an alarm is triggered. Use the AWS SDK tools to integrate your application with Amazon SNS and send messages to the first topic so that on-call engineers receive alerts.
D) Create an Amazon SNS topic for each on-call group, and configure each of these with the team member emails as subscribers. Create another Amazon SNS topic and configure your CloudWatch alarms to notify this topic when triggered. Create an HTTP subscriber to this topic that notifies your application via HTTP POST when an alarm is triggered. Use the AWS SDK tools to integrate your application with Amazon SNS and send messages to the correct team topic when on shift.