题目

 On Sara’s arrival at the airport. Her husband, ___ and waiting in the hall, stood up and came toward her. A .having seated       B. seating        C. to sear        D. seated 答案：D有三个轻小物体，两两靠近时都能相互吸引，则它们的带电情况是（　　）A．两个正带电，另一个带负电B．两个负带电，另一个带正电C．有两个带电，另一个不带电D．有一个带电，另两个不带电