单选题If the speakers in an installation are out of phase， this means that（）A
the subwoofer is at the wrong angle.B
the front and rear speakers are reversed.C
the polarity of the speakers are reversed.D
the angle of the speakers are incorrect.
题目内容(请给出正确答案)
单选题
If the speakers in an installation are out of phase， this means that（）
