using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}

​

public class Form

{}

​

public class PrimaryClass : Form

{

    public void PrimaryClassMethod()

    {

        Console.WriteLine("Method from Primary Class");

    }

}

​

public class SecondaryClass : PrimaryClass

{

    public void CallPrimaryClassMethod()

    {

        this.PrimaryClassMethod();

    }

​

}