A、數(shù)據(jù)線接口接觸不良、處理板破損、調(diào)制解調(diào)器損壞、數(shù)據(jù)傳輸通道故障
	B、數(shù)據(jù)線接口接觸問題、處理板損壞、調(diào)制解調(diào)器損壞、數(shù)據(jù)傳輸通道故障
	C、數(shù)據(jù)線接口問題、處理板損壞、調(diào)制解調(diào)器損壞、數(shù)據(jù)傳輸通道故障
	D、數(shù)據(jù)線接觸不良、處理板損壞、調(diào)制解調(diào)器損壞、數(shù)據(jù)傳輸通道故障
 
                            