Which of the following BEST describes an extranet?

A$.$ A software and hardware system that prevents outsiders from accessing a company's network

B$.$ A tool that searches Web pages containing the user's search terms and then displays pages that match

C$.$ A private network of internal Web sites and other sources of information available to a company's employees

D$.$ An Internet connection allowing outsiders limited access to a firm's internal information system

E$.$ A delivery system linked to production schedules