What should a solutions architect do to meet these requirements?

A gaming company has multiple Amazon EC2 instances in a single Availability Zone for its multiplayer game that communicates with users on Layer 4. The chief technology officer (CTO) wants to make the architecture highly available and cost-effective

What should a solutions architect do to meet these requirements? (Select TWO.)
A . Increase the number of EC2 instances
B . Decrease the number of EC2 Instances
C . Configure a Network Load Balancer in front of the EC2 instances.
D . Configure an Application Load Balancer In front of the EC2 instances
E . Configure an Auto Scaling group to add or remove Instances in multiple Availability Zones automatically

Answer: C,E