阅读下面短文，掌握其大意，然后从21―30各题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。

Wouldn't it be great if we didn'thave to remember passwords （密码）ever again？If we could just sit in front ofour computers and be  21    loggedin （登录? Crave mentions how NECSoftBiodeLogon system uses face recognition technology to log you on to Windows,rather than using a  22  All you need is a webcam and yourpretty face to   23   your PC． No more 24   , confusing passwords to remember or change everyfew months.

After doing a little research, Ifound this type of  25   already available toconsumers via a relatively  26   applicationcalled FaceCode. The  27 requiresthe use of a webcam to recog- nize and log PC users into their systems. You canadd as many  28  as you want, provided they eachhave a Windows account. If the system   29   torecognize your  30  , you can recall the Windows username and password by using a hot-key combination.