What is the function of the 'terraform destroy' command?

The 'terraform destroy' command is specifically designed to remove all the resources that are defined in the Terraform configuration. When this command is executed, Terraform takes a look at the current state of the infrastructure as recorded in its state file and then systematically tears down all the resources that were provisioned. This action is particularly useful when you want to dismantle your entire infrastructure setup and ensure that it no longer exists, for example, after a testing phase or when a project is completed.

The other options don't accurately reflect the function of the 'terraform destroy' command. Deleting the configuration file itself does not happen with this command; instead, the command focuses on the resources created. Similarly, while it interacts with the state file to determine what resources to delete, it does not remove the state files themselves from the local directory. Lastly, 'terraform destroy' does not reset the Terraform environment, as resetting typically refers to clearing the local state or configurations rather than directly removing infrastructure resources. Therefore, option B encapsulates the core functionality of the command accurately.