The case is that the form contains select which is optional and if user selects one option from select but wants to undo that, should list contain blank option or "none" option or how this should be handled?
This is a good question that makes ink flow.
As it always depend on the context of your form, I would answer with some advices and reading, like:
- Avoid a reset button on the form, even if you didn't mention this, just as reminder
- You can make this specific entry resettable,
- You can offer a default choice that will be always available for the user.
For instance, if your question is:
What's your one and only favourite color?
Options would be:
- I don't have one
The first one would be the one by default. Of course you need to work on a neutral default answer depending on the question you ask.
Reading suggestion:https://www.nngroup.com/articles/reset-and-cancel-buttons/ Avoid placeholders in any case.
By the way, it's the same issue with radio buttons: when the answer is optional, you should always prepare a default neutral option selected by default.
I hope this small answer helps you.
Have a great day!