Csharp 带有嵌套元素的 XML Linq

我正在try 将格式如下的XML文件加载到数据表:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<controls:controls xmlns="http://scap.nist.gov/schema/sp800-53/2.0"
                   xmlns:controls="http://scap.nist.gov/schema/sp800-53/feed/2.0"
                   xmlns:xhtml="http://www.w3.org/1999/xhtml"
                   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                   pub_date="2017-08-01"
                   xsi:schemaLocation="http://scap.nist.gov/schema/sp800-53/feed/2.0 http://scap.nist.gov/schema/sp800-53/feed/2.0/sp800-53-feed_2.0.xsd">
   <controls:control>
      <family>ACCESS CONTROL</family>
      <number>AC-1</number>
      <title>POLICY AND PROCEDURES</title>
      <baseline>LOW</baseline>
      <baseline>MODERATE</baseline>
      <baseline>HIGH</baseline>
      <baseline>PRIVACY</baseline>
      <statement>
         <description/>
         <statement>
            <number>AC-1a.</number>
            <description>Develop, document, and disseminate to [Assignment: organization-defined personnel or roles]:</description>
            <statement>
               <number>AC-1a.1.</number>
               <description>[Selection (one or more): Organization-level; Mission/business process-level; System-level] access control policy that:</description>
               <statement>
                  <number>AC-1a.1.(a)</number>
                  <description>Addresses purpose, scope, roles, responsibilities, management commitment, coordination among organizational entities, and compliance; and</description>
               </statement>
               <statement>
                  <number>AC-1a.1.(b)</number>
                  <description>Is consistent with applicable laws, executive orders, directives, regulations, policies, standards, and guidelines; and</description>
               </statement>
            </statement>
            <statement>
               <number>AC-1a.2.</number>
               <description>Procedures to facilitate the implementation of the access control policy and the associated access controls;</description>
            </statement>
         </statement>
         <statement>
            <number>AC-1b.</number>
            <description>Designate an [Assignment: organization-defined official] to manage the development, documentation, and dissemination of the access control policy and procedures; and</description>
         </statement>
         <statement>
            <number>AC-1c.</number>
            <description>Review and update the current access control:</description>
            <statement>
               <number>AC-1c.1.</number>
               <description>Policy [Assignment: organization-defined frequency] and following [Assignment: organization-defined events]; and</description>
            </statement>
            <statement>
               <number>AC-1c.2.</number>
               <description>Procedures [Assignment: organization-defined frequency] and following [Assignment: organization-defined events].</description>
            </statement>
         </statement>
      </statement>
</controls:control>

我能够提取家庭和其他值，但当我试图访问这些语句时，我什么也得不到.我需要创建一个表，其中每个语句值都在一行中，父值也在该行中，如Family和TITLE.

这就是我所得到的:

        string ns = "http://scap.nist.gov/schema/sp800-53/feed/2.0";

        XDocument xdoc = XDocument.Load("80053.xml");

        var ccidata = xdoc.Descendants(XName.Get("control", ns))
            .Descendants("statement")
            .Select(i => new
            {
                family = i?.Parent?.Element("family")?.Value,
                number = i?.Element("number")?.Value,
            }).ToList();

如果您能给我指点，我将不胜感激.