Learn HTML by Building a Cat Photo App - Step 46

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Your code so far

<html>
  <body>
    <h1>CatPhotoApp</h1>
    <main>
      <section>
        <h2>Cat Photos</h2>
        <!-- TODO: Add link to cat photos -->
        <p>Click here to view more <a target="_blank" href="https://freecatphotoapp.com">cat photos</a>.</p>
        <a href="https://freecatphotoapp.com"><img src="https://cdn.freecodecamp.org/curriculum/cat-photo-app/relaxing-cat.jpg" alt="A cute orange cat lying on its back."></a>
      </section>
      <section>
        <h2>Cat Lists</h2>
        <h3>Things cats love:</h3>
        <ul>
          <li>cat nip</li>
          <li>laser pointers</li>
          <li>lasagna</li>
        </ul>
        <figure>
          <img src="https://cdn.freecodecamp.org/curriculum/cat-photo-app/lasagna.jpg" alt="A slice of lasagna on a plate.">
          <figcaption>Cats <em>love</em> lasagna.</figcaption>  
        </figure>
        <h3>Top 3 things cats hate:</h3>
        <ol>
          <li>flea treatment</li>
          <li>thunder</li>
          <li>other cats</li>
        </ol>
        <figure>
          <img src="https://cdn.freecodecamp.org/curriculum/cat-photo-app/cats.jpg" alt="Five cats looking around a field.">
          <figcaption>Cats <strong>hate</strong> other cats.</figcaption>  
        </figure>
      </section>
      <section>
        <h2>Cat Form</h2>
        <form action="https://freecatphotoapp.com/submit-cat-photo">
          <label><input type="radio">indoor<id=indoor></label>
          <input type="text" name="catphotourl" placeholder="cat photo URL" required>
          <button type="submit">Submit</button>
        </form>
      </section>
    </main>
  </body>
</html>

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36 Edg/105.0.1343.53

Challenge: Learn HTML by Building a Cat Photo App - Step 46

Link to the challenge:

the instructions say:

Add an id attribute with the value indoor to the radio button. When elements have multiple attributes, the order of the attributes doesn’t matter.

So all you have to do is to remember that HTML attributes are added to the opening tag.
You have added other HTML attributes before such as when you added href to the anchor tag or when you add src to img tag.

Look at any of your old code and see the pattern of how to add an attribute then do the same here.