VFB Pro 3.3.8 has been released and is now available for download. This update brings back a feature long-time users of VFB Pro or the free version will recognize along with some data integrity improvements and usability enhancements.
In addition to being able to select Google reCAPTCHA to protect your forms from unwanted SPAM, VFB Pro now gives you the option to enable the "Simple CAPTCHA" which requires no API keys or special configuration. If the user fails to enter a correct answer, the form cannot be submitted (sounds familiar).
Check your WordPress dashboard for the latest updates.