waha1ha1

C knows the answer by deducing D is not yelling out the answer.
! }9 F- W+ C5 a  n; r, o; [0 ?That means D is not sure the answer by seeing one white and one black.tvb now,tvbnow,bttvb7 a6 }. P) q7 M% J5 ?: ]
C saw B is wearing the white, hence he is wearing the black