A) Implement data locality controls to keep PII in specific regions, use multiple identity providers for failover, and enable just-in-time provisioning
B) Deploy a single identity provider with global replication, implement end-to-end encryption, and use SAML for federation
C) Use multiple independent identity providers per region, implement OAuth 2.0, and enable cross-region authentication
D) Deploy a hybrid solution with on-premises identity servers syncing to cloud providers, using regional data centers and active-active configuration