If a namespace is present in a library then which of the following is the correct way to use the elements of the namespace?

1. using System.Windows.Forms; 
   ListBox lb = new ListBox();

2. using LBControl = System.Windows.Forms;
   LBControl lb = new LBControl();

3. System.Windows.Forms.ListBox lb = new System.Windows.Forms.ListBox();

4. using LBControl lb = new System.Windows.Forms.ListBox;

5. using LBControl = System.Windows.Forms.ListBox; 
   LBControl lb = new LBControl();

import System; 
namespace CuriousTabConsoleApplication
{ 
    class MyProgram
    { 
        static void Main(string[] args)
        { 
            Console.WriteLine("Hello C#.NET");
        } 
    } 
}

using System;
namespace CuriousTabConsoleApplication
{ 
    class MyProgram
    { 
        static void Main(string[ ] args)
        { 
            WriteLine("Hello C#.NET");
        } 
    } 
}

using System.Console; 
namespace CuriousTabConsoleApplication
{ 
    class MyProgram
    { 
        static void Main (string[ ] args)
        { 
            WriteLine("Hello C#.NET");
        } 
    } 
}

using System;
namespace CuriousTabConsoleApplication
{ 
    class MyProgram
    { 
        static void Main(string[] args)
        { 
            Console.WriteLine("Hello C#.NET");
        }
    }
}

using Microsoft.VisualBasic;
using System.Windows.Forms;
MessageBox.Show("Wait for a" + ControlChars.CrLf + "miracle");

using System.Windows.Forms;
using CtrlChars = Microsoft.VisualBasic.ControlChars; 
MessageBox.Show("Wait for a" + CrLf + "miracle");

using Microsoft.VisualBasic; 
using System.Windows.Forms; 
CtrlChars = ControlChars;
MessageBox.Show("Wait for a" + CtrlChars.CrLf + "miracle");

using Microsoft.VisualBasic; 
using System.Windows.Forms; 
CtrlChars = ControlChars; 
MessageBox.Show ("Wait for a" + CrLf + "miracle");

using System.Windows.Forms;
using CtrlChars = Microsoft.VisualBasic.ControlChars; 
MessageBox.Show("Wait for a" + CtrlChars.CrLf + "miracle");

1. System.Web
2. System.Process
3. System.Data
4. System.Drawing2D
5. System.Drawing3D

1. Classes must belong to a namespace, whereas structures need not.
2. Every class, struct, enum, delegate and interlace has to belong to some or the other namespace.
3. All elements of the namespace have to belong to one file.
4. If not mentioned, a namespace takes the name of the current project.
5. The namespace should be imported to be able to use the elements in it.