Which combination of steps will result in a highly available architecture that meets all the requirements?
(Choose two.)
Create a cross-Region read replica of the database in the secondary Region. Configure an AWS Lambda function in the secondary Region to promote the read replica during a failover event.
In the primary Region, create a health check on the database that will invoke an AWS Lambda function when a failure is detected. Program the Lambda function to recreate the database from the latest database snapshot in the secondary Region and update the Route 53 host records for the database.
Create an AWS Lambda function to copy the latest automated backup to the secondary Region every 2 hours.
Create a failover routing policy in Route 53 for the database DNS record. Set the primary and secondary endpoints to the endpoints in each Region.
Create a hot standby database in the secondary Region. Use an AWS Lambda function to restore the secondary database to the latest RDS automatic backup in the event that the primary database fails.
Explanations:
Creating a cross-Region read replica provides high availability and can be promoted to a standalone database during a failover, meeting the RTO and RPO requirements.
Recreating the database from a snapshot does not meet the RTO requirement of 15 minutes, as restoring from a snapshot may take longer.
Copying automated backups every 2 hours does not directly provide a highly available architecture and would not allow for a fast failover, failing the RTO requirement.
A failover routing policy in Route 53 ensures that traffic is routed to the secondary Region if the primary Region fails, contributing to high availability.
Using a hot standby that relies on restoring from backups does not meet the RTO requirement, as restoring a database from a backup may take longer than 15 minutes.
I organize that the answer is:
Create a cross-Region read replica of the database in the secondary Region. Configure an AWS Lambda function in the secondary Region to promote the read replica during a failover event.