IEnumerable <TSource> Concat <TSource>是否保留元素的顺序？

using System;
using System.Linq;

class Program
{
    static void Main()
    {
        string[] firstSequence = { "one", "two", "three" };
        string[] secondSequence = { "four", "five", "six" };

        var result = firstSequence.Concat(secondSequence);

        foreach (var item in result)
        {
            Console.WriteLine(item);
        }
    }
}

one
two
three
four
five
six