Anti Spam Security Question

Hi
I'd like to put a security question on my contact forms to avoid spam.
(Prefer this to a captcha)

I can select random record with a question and answer field but can't find a way to validate a user's input against the answer field.
I thought the Server Validation might be the answer but cannot see how to do it.
Any help or pointer in the right direction appreciated.
Many thanks
Clive

You need to use the CSS Form Builder wizard for this.

Click the edit icon next to the Choose a form option to edit the form contents.

select the group the security question should be part of and click edit.


Add a new filed to the set it should be part of an set the type to security question.