CompTIA A+ 220-901

Answer: C - 2004:7230::0006::1FF0 is not a correctly written IPv6 address.

Key Takeaway - All of the IPv6 addresses written above represent the same IPv6 address, except answer choice C. B shows the IPv6 address fully written-out, with eight “hextets” of 32-bits each. When writing out IPv6, you are allowed to truncate consecutively written groups of 0s as double colons, but you may only employ the rule once (otherwise it becomes impossible to determine where the removed zeros belong). Hence, answer choices A and D are acceptable. Answer D also demonstrates another rule of truncation for IPv6 addresses, which allows the removal of leading zeros (0006 is truncated to simply 6).