An organization is evaluating the use of Google Cloud Platform (GCP) for certain IT workloads. A well-established directory service is used to manage user identities and lifecycle management. This directory service must continue for the organization to use as the "source of truth" directory for identities. Which solution meets the organization`s requirements? 

Answer options:

A. Google Cloud Directory Sync (GCDS)
B. Cloud Identity
C. Security Assertion Markup Language (SAML)
D. Pub/Sub

B

Reference: https://cloud.google.com/solutions/federating-gcp-with-active-directory-introduction