A company manages a large fleet of Amazon EC2 Linux instances in its production AWS...

Option A directly matches all requirements with the least extra infrastructure:

State Manager is the Systems Manager capability for defining and maintaining a desired configuration by running associations on a schedule (for example, hourly). That satisfies the “run periodically” requirement in a managed way across a large fleet.

The AWS-ApplyChefRecipes Systems Manager document is specifically intended to run Chef recipes/cookbooks on managed instances without requiring you to run your own Chef server infrastructure . You can point it at a cookbook source (such as an artifact/repo location) and have Systems Manager handle execution on the instances.

Why the other options aren’t correct:

B is not the right mechanism for periodic Chef cookbook execution. Installing an application package and running a “repair action” via Run Command is not the purpose-built Chef cookbook runner, and it’s more brittle/DIY than State Manager associations.

C ( AWS-RefreshAssociation ) is used to refresh/reevaluate association metadata/targets; it does not itself execute Chef cookbooks as the compliance mechanism.

D is for OS patching compliance (Patch Manager/patch policies), not for applying Chef cookbooks that detect and remediate configuration drift.