题目

Didn't you see the man __________________ I talked with just now? 答案：who/whom下列说法错误的是（　　）A．对角线互相垂直的四边形是菱形B．一组邻边相等的矩形是正方形C．对角线互相垂直的矩形是正方形D．对角线互相平分且相等的四边形是矩形