Which of the following is a valid IPv6 address?

Which of the following is a valid IPv6 address?

A.
45CF. 6D53: 12KP: AFC7: E654: BB32: 543C. FACE

B.
45CF. 6D53: 12CD. AFC7: E654: BB32: 54AT: FACE

C.
45CF. 6D53: 12CD. AFC7: E654: BB32: 543C. FACE

D.
123.111.243.123