waha1ha1

C knows the answer by deducing D is not yelling out the answer.tvb now,tvbnow,bttvb, _* A  \2 @! ~' c$ Q
That means D is not sure the answer by seeing one white and one black.
" N# l4 v1 n% f7 B公仔箱論壇C saw B is wearing the white, hence he is wearing the black