Which of the following can be stored in a Docker volume?

Docker volumes are specifically designed for storing persistent data that is used by containers. This includes application data and files that need to be retained even if the container is destroyed or recreated. By utilizing volumes, you can manage and keep the data separate from the container's lifecycle, ensuring that important information is not lost when the container is stopped or removed.

Volumes are especially important for scenarios where applications require data to be consistently available, such as databases or user-generated content. They can be shared among multiple containers, making data management and application scaling easier.

The other options do not align with the purpose of a Docker volume. Container metadata refers to details about the container itself and doesn't require persistent storage in the same way that application data does. Container images are the blueprints for containers but do not represent data created or modified by the application. Docker configurations typically include settings such as environment variables or networking details and are not stored within a volume, but rather managed through configuration files or Docker Compose. Thus, application data and files are the correct and primary use case for Docker volumes.