Acorporation needs an operating system that allows the various teams in its office to network and collaborate on projects. which operating system should the corporation choose?

The answer is Network Operating System.

Explanation:

Network OS supports network operations and functions. Such operations includes, file-sharing, permission assignments, user groups and privileges, and network security implementation that is needed. Network OS also offers patches, fixes, network monitoring and support unlike with other OS that is focusing more on interface, errors and bugs fix. To install network OS, you need to set up a client and a server computer first.  

To implement network OS in the given scenario, each user will be assigned in a group. Each group is categorized per department to make them communicate and share files within their members. Then there will be a bigger group which involved all departments. The reason why user must be grouped is to prevent other departments to see confidential files which is only authorized to access by certain members. Collaborations can also be conducted per group or to the whole office.  

Example of network OS is Microsoft Server Operating Systems.