I have a whois form in my site that enables users to query for domain name availability and if available gives them the option to request for registering it. The whois form is inserted via shortcodes.
My problem is that I want to protect this form from spam bots by hiding the form until the user solves a simple math question or enters a captcha.
I made a lot of research on the internet but found nothing on hiding content for visitors until they prove their humanity. All I found is to hide content for un-logged-in users, which is not my case, because I want to give general visitors (not members) the ability to use the whois form and prevent spam bots at the same time.
Any help or guide lines is greatly appreciated.
Many Many Thanks,