title: How do I deselect a whole group of radio buttons when a user clicks on some other button?
body: <p>Let's say I have a form where people can choose what kind of pet they want and - optionally - indicate a breed and age like this:</p>
  
  <pre><code>    &lt;input type="radio" name="pet" value="P70" /&gt; Cat&lt;br&gt; 
          Breed:&lt;br&gt; 
          &lt;input type="radio" name="catbreed" value="P71" /&gt; Persian  
          &lt;input type="radio" name="catbreed" value="P72" /&gt; Siamese
          &lt;input type="radio" name="catbreed" value="P73" /&gt; Tabby  &lt;br&gt; 
          Age:&lt;br&gt; 
          &lt;input type="radio" name="catage" value="P74" /&gt; Kitten
          &lt;input type="radio" name="catage" value="P75" /&gt; Adult
          &lt;p&gt;
  
      &lt;input type="radio" name="pet" value="P78" /&gt; Dog&lt;br&gt;
          Breed:&lt;br&gt;
          &lt;input type="radio" name="dogbreed" value="P79" /&gt; German Shepherd
          &lt;input type="radio" name="dogbreed" value="P80" /&gt; Golden Retriever
          &lt;input type="radio" name="dogbreed" value="P81" /&gt; Poodle  &lt;br&gt; 
          Age:&lt;br&gt; 
          &lt;input type="radio" name="dogage" value="P82" /&gt; Puppy
          &lt;input type="radio" name="dogage" value="P83" /&gt; Adult
  </code></pre>
  
  <p>If they first choose "cat" and then switch to "dog," the radio buttons will take care of that.  But if they've already selected a breed or age for the cat, there's no way to deselect that.  (And they're already 70 questions into the form, so resetting the whole thing is a hassle.)</p>
  
  <p>How can I add a javascript that will deselect the breed and age for one pet if users change their minds and switch to a different pet?</p>
  
  <p>UPDATE: I probably wasn't clear enough in my question.  I'm not looking to add a button to reset the breed and age values, I just want it to be automatic and idiot-proof.  Clicking "cat" should erase any values that might be there for dogbreed or dogage, and clicking "dog" should erase any values that are there for catbreed or catage. </p>