Which Microsoft .NET namespace contains the classes required to perform the following tasks: Creating a TCP or UDP network connection Transmitting data

Which Microsoft .NET namespace contains the classes required to perform the following
tasks:
Creating a TCP or UDP network connection
Transmitting data

A.
System.Net.Cache

B.
System.Net.PeerToPeer

C.
System.Net.Sockets

D.
System.Net.Configuration

Explanation:
http://msdn.microsoft.com/en-us/library/system.net.sockets(v=vs.95).aspx