{TAIL ~ A challenge question} can be presented to {HEAD ~ the cardholder}, and the cardholders response can be verified 
{ TAIL ~ A challenge question } can be presented to { HEAD ~ the cardholder } , and the cardholders response can be verified
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH