C# 从linq到xml仅选择一个随机节点

我有一个XML文件，我只想选择一个随机节点。看起来我就快到了，但是带有var的foreach正在循环。如何仅选择一个节点并返回它

XML:

提前感谢,

---

EP

您可以选择一个随机元素，而不是设置排序

var qas = questions.Descendants("qa");
int qaCount = qas.Count();
h = qas.ElementAt(rnd.Next(0, qaCount - 1)).Element("q").Value;

public class human_check
{

    public static string get_q()
    {
        try
        {
            string h = string.Empty;
            Random rnd = new Random();
            XDocument questions = XDocument.Load(@"C:\Users\PETERS\Desktop\human_check.xml");
            var random_q = from q in questions.Descendants("qa")
                           select new
                           {
                               question = q.Descendants("q").OrderBy(r => rnd.Next()).First().Value
                           };

            foreach (var rq in random_q)
            {
                h = rq.question.ToString();
            }

            return h;

        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

}

var random_q = (from q in questions.Descendants("qa")
                select q).OrderBy(r => rnd.Next()).First();

h = random_q.Descendants("q").SingleOrDefault().Value.ToString();

var qas = questions.Descendants("qa");
int qaCount = qas.Count();
h = qas.ElementAt(rnd.Next(0, qaCount - 1)).Element("q").Value;