Rationale for Correct Answer (B):
terraform import allows Terraform to associate existing resources (created outside of Terraform or by another tool) with a Terraform configuration by writing them into the state file. After import, Terraform can manage those resources.
Analysis of Incorrect Options:
A. From one state file to another: Incorrect, import does not transfer between state files.
C. Importing a module: Incorrect, modules are defined in configuration, not imported.
D. Import all infrastructure: Incorrect, import is per-resource, not bulk.
E. Provider configuration transfer: Incorrect, provider configs are in .tf files, not imported with this command.
Key Concept:
The terraform import command bridges existing resources with Terraform state management.