A、<img width="67" height="23" src="http://admintk.100xuexi.com/UpLoadImage/2013-05-07/f6109fd8-a79a-4d42-95a5-171ab02b388c.png" />
B、<img width="83" height="22" src="http://admintk.100xuexi.com/UpLoadImage/2013-05-07/24b43027-4178-43a3-86d2-f963f4214a62.png" />
C、<img width="73" height="21" src="http://admintk.100xuexi.com/UpLoadImage/2013-05-07/063dab5a-ceed-4d09-94a6-8feb37b24c6d.png" />
D、<img width="75" height="21" src="http://admintk.100xuexi.com/UpLoadImage/2013-05-07/bedd7711-78e1-49fb-aa97-e6c3bedefcf6.png" />