public class SomeClass

{

    private static readonly Apple a, c;

    private static Orange _b;

    private readonly Orange b;

​

    static SomeClass()

    {

        a = new Apple();        

        _b = new Orange(a.getDna());

        c = new Apple(_b.getDna());

    }

​

    public SomeClass()

    {

        b = _b;

        _b = null;

    }

​

    public class Apple

    {

        public Apple(object o = null) {}

        public object getDna()

        {

            return new object();

        }

    }

​

    public class Orange

    {

        public Orange(object o = null) { }

        public object getDna()

        {

            return new object();

        }

    }

    public void Main() 

    {

        var sc = new SomeClass();

        System.Console.WriteLine(_b == null);

        System.Console.WriteLine(b == null);

    }

}