Holly has discovered that a highly privileged dynamic credential with a very long lease time...

Comprehensive and Detailed in Depth Explanation:

To invalidate a specific dynamic credential without affecting others, Holly should use the vault lease revoke command with the exact lease ID. The HashiCorp Vault documentation states: "The lease revoke command revokes the lease on a secret, invalidating the underlying secret. To revoke a lease, you can specify the path and lease ID attached to the creds." The command vault lease revoke aws/creds/admin/27e1b9a1-27b8-83d9-9fe0-d99d786bdc83 targets the specific credential by its unique lease ID, ensuring precision without broader impact.

Deleting the credential on the cloud platform (B) doesn’t guarantee Vault recognizes it as revoked. vault lease revoke -all (C) revokes all leases, affecting unrelated credentials. vault lease revoke aws/creds/admin/* (D) revokes all leases under that path, potentially impacting other valid credentials. Thus, A is the correct command.