What should Erick use to manage an application consisting of multiple containers in a Docker Swarm?

Using a stack is the appropriate choice for managing an application that consists of multiple containers in Docker Swarm because a stack allows for the deployment and management of multiple services, networks, and volumes that are needed to run an application effectively. In Docker Swarm, a stack is defined by a Compose file that specifies how the containers should be configured, how they interact, and any necessary resources.

By utilizing a stack, Erick can deploy, update, and manage the entire application as a single unit, rather than handling each individual container separately. This approach simplifies orchestration, scaling, and application management, which is essential when working with multiple interdependent containers in a complex application environment.

The other options do not encompass the full range of management capabilities needed for multiple containers. A service, for instance, refers to a specific containerized application that is managed by Docker Swarm, while a container represents a single instance of that application. A network is used to enable communication between containers but does not provide the higher-level orchestration features that a stack does.