C knows the answer by deducing D is not yelling out the answer.os.tvboxnow.com( ]9 m4 j/ g% n5 f/ \
That means D is not sure the answer by seeing one white and one black.tvb now,tvbnow,bttvb% a2 z. X% {% V7 v5 y( @. S
C saw B is wearing the white, hence he is wearing the black |