Exam AWS Certified Solutions Architect - Professional topic 1 question 749 discussion

A solutions architect is evaluating the reliability of a recently migrated application running on AWS. The front end is hosted on Amazon S3 and accelerated by
Amazon CloudFront. The application layer is running in a stateless Docker container on an Amazon EC2 On-Demand Instance with an Elastic IP address. The storage layer is a MongoDB database running on an EC2 Reserved Instance in the same Availability Zone as the application layer.
Which combination of steps should the solutions architect take to eliminate single points of failure with minimal application code changes? (Choose two.)