C knows the answer by deducing D is not yelling out the answer. # |# L5 F2 l; R" [$ j ros.tvboxnow.comThat means D is not sure the answer by seeing one white and one black.公仔箱論壇. A3 E }/ Q# x5 r: i4 |- i" @0 o
C saw B is wearing the white, hence he is wearing the black
C, because he saw B's hat is white and he knows D can see the color of B's and his hat. If B and his hat has the same color, D would speak out. But D kept silent, so C knows that his hat's color must be different.