A company has 100 client computers that run Windows 8. The client computers are
members of a workgroup.
A custom application requires a Windows Firewall exception on each client computer.
You need to configure the exception on the client computers without affecting existing
firewall settings.
Which Windows PowerShell cmdlet should you run on each client computer?

A.
New-NetFirewallRule

B.
Set-NetFirewallSetting

C.
Set-NetFirewallRule

D.
Set-NetFirewallProfile

E.
New-NetIPSecMainModeRule

Explanation:
Creates a new inbound or outbound firewall rule and adds the rule to the target computer.

http://technet.microsoft.com/en-us/library/jj554908.aspx
New-NetFirewallRule -DisplayName “Allow Inbound Telnet” -Direction Inbound -Program
%SystemRoot%\System32\tlntsvr.exe -RemoteAddress LocalSubnet -Action Allow