You have just upgraded the version constraint of a provider in an existing Terraform configuration.

Detailed Explanation:

Rationale for Correct Answer: terraform init -upgrade tells Terraform to disregard the previously selected versions in the dependency lock file when appropriate and consider newer provider versions that satisfy the configured version constraints.

Analysis of Incorrect Options (Distractors):

B: terraform apply executes actions from an execution plan; it is not the command for deliberately upgrading provider dependencies.

C: terraform plan previews infrastructure changes but does not perform a provider upgrade.

D: terraform refresh concerns state synchronization and does not install a newly selected provider version.

Key Concept: Provider dependency installation, version constraints, and the dependency lock file.