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>
    <alltransclusions gatcontinue="CCIR_Table|2066" />
  </query-continue>
  <query>
    <pages>
      <page pageid="94" ns="0" title="FM Broadcast Radio" />
      <page pageid="95" ns="0" title="Amplitude Modulation (AM)" />
      <page pageid="107" ns="0" title="PAL Broadcast" />
      <page pageid="109" ns="0" title="Digital Audio Broadcasting (DAB)" />
      <page pageid="115" ns="0" title="Digital Radio Mondiale (DRM)" />
      <page pageid="206" ns="0" title="Digital Video Broadcasting — Terrestrial (DVB-T)" />
      <page pageid="553" ns="0" title="ATSC Broadcast" />
      <page pageid="2158" ns="0" title="NTSC Broadcast" />
      <page pageid="2171" ns="0" title="SECAM" />
      <page pageid="8519" ns="0" title="5G Broadcast (MBMS) Multimedia Broadcast / Multicast Service" />
    </pages>
  </query>
</api>