We are currently developing a website for a client and using the ReCaptcha field data type within Contour for the forms. However the client really doesn't like this captcha control and has asked if we can implement one of the "human question" type captchas where it asks you a question such as "What does 2 + 7 make"

Has anyone implemented a captcha control like this before in Contour, or does anyone have any ideas how I would go about implementing this type of functionality?