Site administrators are able to create and modify user groups in an organization managed project at Riverton Systems.

Site administrators manage global user and group settings across the site and they can create, edit, and delete groups as well as assign product access and permissions that apply to organization managed projects.

Project administrators are incorrect because they manage settings and configurations within a specific project and they do not have the global permissions required to create or modify site level user groups.

Jira administrators is incorrect because Jira admin roles focus on product configuration and schemes within Jira and do not inherently grant the site wide ability to manage user groups unless those admins also have site administrator rights.

Organization administrators is incorrect because organization admins manage organizational settings and user access at the organization level but they do not automatically have the site level capability to create and maintain groups for the site unless they also hold site administrator privileges.

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