Final answer:
The option not supported by an organization's intranet information portal is public website access. An intranet typically includes employee communication, document sharing, and collaboration tools, but not public access, which is meant for external audiences.
Step-by-step explanation:
All of the following would typically be supported by an organization's intranet information portal except public website access. However, because an intranet is designed for private use within an organization, it would not typically include public website access, which is intended for external audiences and is not a secure or private means of communication or information storage for an organization's internal needs.