The correct answer is All sites share the same organization administrators.

All sites share the same organization administrators because Atlassian organizations provide centralized administration and the organization administrators role spans every site in that organization. The organization administrators can manage users and organization settings and they have visibility across all sites that belong to the same organization.

Each site uses identical default user groups is incorrect because sites can have different group and permission configurations. Default groups are not enforced to be identical across separate site instances and site level settings can diverge.

Every site is linked to a single shared sandbox environment is incorrect because sandboxes are provisioned and scoped by product and by site. Sandboxes are not inherently a single shared environment across multiple sites and availability depends on the product plan and configuration.

All sites are managed by the same Jira product administrators is incorrect because product administrator roles are assigned per site and per product. Different sites can therefore have different Jira product administrators even when they belong to the same organization.

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