A healthcare organization would like to work with another healthcare organization without needing to maintain...

The correct answer is D — Federated authentication.

WGU Cybersecurity Architecture and Engineering (KFO1 / D488) explains that federated authentication allows two or more organizations to share identity information securely withoutneeding to maintain separate user accounts for external users. It supports cross-organizational access based on trusted identity providers.

Cloud identity providers (A) offer centralized authentication but don't address federation directly. SSO (B) simplifies authentication within an organization. MFA (C) adds security but does not enable cross-organization authentication.

Reference Extract from Study Guide:

"Federated authentication enables organizations to share identity information and trust external credentials without the need to manage separate accounts for external users."

— WGU Cybersecurity Architecture and Engineering (KFO1 / D488), Identity Federation and Single Sign-On Concepts

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