Which IPv6 address is valid?

Which IPv6 address is valid?

A.
2031:0:130F::9C0:876A:130B

B.
2001:0db8:0:130H::87C:140B

C.
2001:0db8:0000:130F:0000:0000:08GC:140B

D.
2031::130F::9C0:876A:130B

Explanation: