Additionally, there are many flexible implementation options of {HEAD ~ the challenge response application} that can be adjusted based on {TAIL ~ factors} such as the location of the merchant or the location of the consumer 
adjusted based on
Additionally , there are many flexible implementation options of { HEAD ~ the challenge response application } that can be adjusted based on { TAIL ~ factors } such as the location of the merchant or the location of the consumer
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH