Disable option in select menu

Hi

I have a problem with the select menu in a form.

The options is like this:
Please choose
Option 1
Option 2
Option 3

So the option "Please choose" will be the default option, but I don't want the users to be able to select that.

As it is now it is possible to submit the form, without choosing between options 1-3.

I hope this makes sense :)


P.S.
After looking around the web, it might be possible with the code below, but Contao doesn't seem to support that?

Code:

---

<option disabled="disabled">

---