CAPTCHA is a security tool created by Google to protect your site from robot or malware. Often it will only request the "I'm Not A Robot" tick box option, but if the browser has detected any suspicious activity such as multiple attempts from the same IP address, it'll ask further security selections to be certain. As this is operated by Google, the questions it requests can't been controlled through Payments 2 Us.
We recommend enabling CAPTCHA wherever practical. The additional time spent in the security process can avoid problems later on.
For more information about how Google reCAPTCHA works, go to: https://www.google.com/recaptcha/intro/invisible.html