Valid IPv6 Address

A

Option A: 2031:0:130F::9C0:876A:130B This IPv6 address is valid as it contains eight groups of four hexadecimal digits separated by colons. Double colons (::) can be used to represent consecutive groups of 0s only once in an IPv6 address. In this address, the double colon represents two groups of 0s. The address also falls within the valid range of IPv6 addresses.

Option B: 2001:0db8:0:130H::87C:140B This IPv6 address is invalid as it contains an invalid hexadecimal digit "H" in the third group of digits. IPv6 addresses can only contain digits 0-9 and letters A-F.

Option C: 2001:0db8:0000:130F:0000:0000:08GC:140B This IPv6 address is invalid as it contains an invalid hexadecimal digit "G" in the seventh group of digits. IPv6 addresses can only contain digits 0-9 and letters A-F. Additionally, it has unnecessary leading zeros which can be omitted.

Option D: 2031::130F::9C0:876A:130B This IPv6 address is invalid as it contains multiple instances of double colons (::). IPv6 addresses can only contain one instance of double colons (::) to represent consecutive groups of 0s.