Make field editable in comment form
First, you need 'options' =&gt; array('clarification required', 'clarification isn\'t required') for select because you need options. Then you need to make sure your module name is custom (unless you don't want to expose your module name). Also, you pass your function name to $form['#validate'][] but it ends with _submit (it should be _validate).

There are what I found at the first glance. I didn't check the code.