Your company is planning on moving to the AWS Cloud. One of the Web applications will be launched on a set of EC2 Instances. You need to ensure that the architecture is fault-tolerant and highly available. Which of the following would be considered during the design process. Choose 2 answers from the options given below.

Answer options:

A.Have a Single Availability Zone for the databases
B.Use a load balancer in front of the EC2 Instances
C.Ensure that the EC2 Instances are spread across multiple availability zones
D.Ensure that the EC2 Instances are spread across a single availability zone for better maintenance

Answer - B and C
This is clearly mentioned in the AWS Documentation.
What Is Elastic Load Balancing?
Elastic Load Balancing distributes incoming application or network traffic across multiple targets, such as Amazon EC2 instances, containers, and IP addresses, in multiple Availability Zones. Elastic Load Balancing scales your load balancer as traffic to your application changes over time and can automatically scale to the vast majority of workloads.
Load Balancer Benefits
A load balancer distributes workloads across multiple compute resources, such as virtual servers. Using a load balancer increases the availability and fault tolerance of your applications.
Option A is invalid because it will not increase the availability and fault tolerance of your applications.
Option D is invalid because you need to ensure that the Instances are spread across multiple availability zones.
For more information on load balancing and availability of EC2 Instances, please visit the URL-
https://docs.aws.amazon.com/elasticloadbalancing/latest/userguide/what-is-load-balancing.html
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-increase-availability.html