委托对象错误

我对C#比较陌生，正在尝试学习如何从Dictionary调用delegate。我使用的是<string, Delegate配对。我的测试课程如下：

namespace DelegatesHowTo
{
    class Program
    {
        protected delegate bool ModuleQuery(string parameter);
        static Dictionary<string, ModuleQuery> queryDictionary = new Dictionary<string, ModuleQuery>();
        public Program()
        {
            queryDictionary.Add("trustQuery", new ModuleQuery(queryTrustedStore));
            queryDictionary.Add("tokenQuery", new ModuleQuery(queryTokenStore));
        }
        static void Main(string[] args)
        {
            ModuleQuery MyQuery = new ModuleQuery(queryTrustedStore);
            queryDictionary.TryGetValue("trustQuery", out MyQuery);
            bool testQuery = MyQuery("TestTrusted");
            Console.WriteLine("Trusted: {0}", testQuery);
        }
        static bool queryTrustedStore(string parameter)
        {
            return parameter.Equals("TestTrusted");
        }
        static bool queryTokenStore(string parameter)
        {
            return parameter.Equals("TestToken");
        }
    }
}

然而，线路bool testQuery = MyQuery("TestTrusted");抛出Unhandled Exception: System.NullReferenceException: Object reference not set to an instance of an object. at DelegatesHowTo.Program.Main(String[] args) in c:'...

我的印象是我正在用ModuleQuery MyQuery = new ModuleQuery(queryTrustedStore);实例化一个对象。我想这不是真的吧？有人能为我指明正确的方向吗？如何纠正这种情况？