using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var test = new List<string>();

        if (test?.Contains("Fiets") == true)

        {

            Console.WriteLine("Hello World");

        }

        test = null;        

        if (test?.Contains("Fiets") == true)

        {

            Console.WriteLine("Hello World 2");

        }

        else {

            Console.WriteLine("Hello World 3");

        }

    }

}