You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <allredirects arcontinue="Benito_Pablo_Juárez_and_Adoption" />
  </query-continue>
  <query>
    <allredirects>
      <r ns="0" title="Baiteke and Adoption (under Kiribati)" />
      <r ns="0" title="Barbara La Marr and Adoption" />
      <r ns="0" title="Barbara Strozzi and Adoption" />
      <r ns="0" title="Barbara Walters and Adoption" />
      <r ns="0" title="Barry Evans and Adoption" />
      <r ns="0" title="Basavis and Adoption (under Devadasi)" />
      <r ns="0" title="Bauro and Adoption (under Kiribati)" />
      <r ns="0" title="Bede, the Venerable and Adoption" />
      <r ns="0" title="Ben Andrews and Adoption" />
      <r ns="0" title="Ben Stein and Adoption" />
    </allredirects>
  </query>
</api>