Correct answer - "aws ecs create-service --service-name ecs-simple-service --task-definition
ecs-demo --desired-count 10" : To create a new service you would use this command which creates
a service in your default region called ecs-simple-service. The service uses the ecs-demo task
definition and it maintains 10 instantiations of that task.
"aws ecr create-service --service-name ecs-simple-service --task-definition ecs-demo
--desired-count 10" - This command is referencing a different service called Amazon Elastic
Container Registry (ECR) which's is a fully-managed Docker container registry
"docker-compose create ecs-simple-service" - This is a docker command to create containers for a
service and not a command used in the CLI
"aws ecs run-task --cluster default --task-definition ecs-demo" - This is a valid command but
used for starting a new task using a specified task definition