If you want choice field options to accept a limited number of selections, you can enable this feature from the Form Editor. Once an option is unavailable, it will be grayed out on the form.
If the limit for a choice has been reached, that option is automatically grayed out and cannot be selected anymore by the form users.
You also have the option to Reset every day. Don’t worry, your previous submissions won’t be deleted. They will still be found in Submissions.