Verify the user's answer without plugin solution

Hello. Without plugin solution, how is it possible to verify the user's answer with the verify url and post parameters if the result is not accessible with XMLHttpRequest or iframe content ? Thank you. -- You received this message because you are subscribed to the Google Groups "reCAPTCHA" group. To unsubscribe from this group and stop receiving emails from it, send an email to recaptcha+unsubscribe@googlegroups.com. To post to this group, send email to recaptcha@googlegroups.com. Visit this group at http://groups.google.com/group/recaptcha. For more options, visit https://groups.google.com/groups/opt_out.