--Mom, I can't find my new T-shirt.

--Oh, honey, it__________after you went to see AVATAR. It is still in the dryer.

A．has been washing

B．has washed

C．was to be washed

D．was washed

与恒速/恒频系统相比，变速/恒频发电机系统的风/电转换装置的电气部分变得较为复杂和昂贵。（）