An engineer must configure an ACL that permits packets which include an ACK in the TCP header. Which entry must be included in the ACL?

A.	access-list 110 permit tcp any any eq 21 tcp-ack
B.	access-list 10 permit tcp any any eq 21 established
C.	access-list 110 permit tcp any any eq 21 established
D.	access-list 10 permit ip any any eq 21 tcp-ack