If a class called Point is present in namespace n1 as well as in namespace n2, then which of the following is the correct way to use the Point class?

namespace CuriousTabConsoleApplication
{ 
    class MyProgram
    { 
        static void Main(string[] args)
        { 
            import n1; 
            Point x = new Point();
            x.fun();
            import n2;
            Point y = new Point(); 
            y.fun();
        }
    }
}

import n1; 
import n2;
namespace CuriousTabConsoleApplication
{ 
    class MyProgram
    { 
        static void Main(string[] args)
        {
            n1.Point x = new n1.Point(); 
            x.fun();
            n2.Point y = new n2.Point(); 
            y.fun();
        }
    }
}

namespace CuriousTabConsoleApplication
{ 
    class MyProgram
    {
        static void Main(string[] args)
        {
            using n1;
            Point x = new Point();
            x.fun();
            using n2;
            Point y = new Point();
            y.fun();
        }
    }
}

using n1;
using n2; 
namespace CuriousTabConsoleApplication
{ 
    class MyProgram
    { 
        static void Main(string[] args)
        { 
            n1.Point x = new n1.Point(); 
            x.fun();
            n2.Point y = new n2.Point(); 
            y.fun(); 
        } 
    } 
}