It looks like your entire indentation is off by two. Restart the step, this is what you should see:
<!-- TODO: Add link to cat photos -->
<p>Click here to view more cat photos.</p>
Notice how the body element is indented two spaces in from the html element. But in the HTML you pasted it is not indented, it is lined up with the html element. Did you do anything to cause this?
Regardless, restart the step and be sure to only do one thing, add two spaces in front of the p element. That’s it.
UPDATE: Never mind, I see now that when you use the Ask for Help button, when it automatically puts your HTML in there, it formats the HTML incorrectly, at least as far as we are concerned for this step.
Also, the real issue is that you have added some extra whitespace after the comment. While this technically shouldn’t be a problem, the tests don’t like it.