C knows the answer by deducing D is not yelling out the answer.
7 p* F3 x. g; Q- y9 [" f0 n5 v; p% N5.39.217.77:8898That means D is not sure the answer by seeing one white and one black.tvb now,tvbnow,bttvb1 K7 f: T3 j) D5 `, P
C saw B is wearing the white, hence he is wearing the black |