From the accessibility point of view, you could worry about whether is always better to use a sound or image type verification quiz however, despite of you have fixed the reCAPTCHA <em>Type</em> parameter to <strong>Image</strong> in the <strong>%s</strong> accordion section, Google reCAPTCHA field automatically (and always) allows people that use screen readers to convert the reCAPTCHA quiz into a sound or text type verification field so that, you have not to configure anything else.