When designing a typical three-tier web application, which AWS services and/or features improve availability and reduce the impact failures? (Select TWO.)
A . AWS Auto Scaling for Amazon EC2 instances.
B . Amazon VPC subnet ACLs to check the health of a service.
C . Distributed resources across multiple Availability Zones.
D . AWS Server Migration Service (AWS SMS) to move Amazon EC2 instances into a different Region.
E . Distributed resources across multiple AWS points of presence.
Answer: C,D