设A , B , C均为n阶方阵，，，则的值为（ ）。\n \n \n \n \n \n \n

\n \n \n \n A.\n

\n \n \n

\n \n \n \n B.\n

\n \n \n

\n \n \n \n C.\n

\n \n \n

\n \n \n \n D.\n