Survey can not clear value when switching between options. But also not save data of hidden field

[hieutnk]

Survey can not clear value when switching between options due to not having UI Policies or Client Script.
But when I submit the survey, the taken data is the latest on the survey (the value of hidden question is not saved, but it's also not clear, so it's kinda confusing). Is there any documentation that talks about this mechanism?
Thanks for your support.

[vamshi16]

Hi,

Please check this article.

https://support.servicenow.com/kb?id=kb_article_view&sysparm_article=KB1644137