The correct answer is D. An Enterprise Grid organization can have only one Org Primary Owner. This is the highest-level ownership role for the Enterprise organization and is distinct from Org Owners, Org Admins, Workspace Owners, and Workspace Admins. The number of workspaces in the grid does not change the number of Org Primary Owners. In this scenario, the organization has four workspaces --- Social, Finance, Marketing, and Operations --- but that does not mean there are four Org Primary Owners. Option A incorrectly maps one Org Primary Owner per workspace. Option B has no basis in the role model. Option C is wrong because the organization cannot define an arbitrary number of Org Primary Owners. The Primary Owner concept exists to provide a single ultimate accountable owner for the Enterprise organization, while additional administrative responsibility can be delegated through Org Owner, Org Admin, Workspace Owner, and Workspace Admin roles.

Reference topic: Governance Structure (Owner and Admin Roles) --- Org Primary Owner, Enterprise Grid role hierarchy, ownership accountability, and admin delegation.

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