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>
    <random>
      <page id="10167" ns="0" title="CFS T-Klassen/Klasse 7a 2017-2018/Humanbiologie/Mo, 11.02.19" />
      <page id="7013" ns="0" title="Augen auf im Internet/P-Seminar 2017-19: Facebook und Co: Wie viele Likes bin ICH wert?/Projekttage: Planung und Durchführung" />
    </random>
  </query>
</api>