Simple lock mechanism

//Prints: "SSSSSSSSSSAABABAABABAABABABBBB" (result may vary due to threading)
using System.Threading;
using System;
namespace test
{
    //main class
    class Program
    {
        static void Main(string[] args)
        {
            Q q = new Q();
            for (int i = 0; i < 10; i++)
            {
                Console.Write("S");
                new Thread(delegate() { q.DoStuff(); }).Start();
            }
            Console.ReadKey(true);
        }
    }

    //test class
    public class Q
    {
        private static object lockA;
        private static object lockB;

        public Q()
        {
            lockA = new object();
            lockB = new object();
        }

        public object DoStuff()
        {
            object result;
            lock (lockA)
            {
                result=A();
            }
            lock (lockB)
            {
                return B(result);
            }
        }

        private object A()
        {
            //do long work
            Thread.Sleep(2000);
            Console.Write("A");
            return new object();
        }

        private object B(object ResultA)
        {
            //do long work
            Thread.Sleep(3000);
            Console.Write("B");
            return new object();
        }
    }
}