A、<img width="19" height="37" src="http://admintk.100xuexi.com/UpLoadImage/2016-08-19/8adf04ae-647f-43d9-beea-f518b925b89d.png" />
B、<img width="20" height="36" src="http://admintk.100xuexi.com/UpLoadImage/2016-08-19/3d170fc0-35d4-40f4-b570-71b3452afd71.png" />
C、<img width="20" height="37" src="http://admintk.100xuexi.com/UpLoadImage/2016-08-19/ad7cd9f8-d496-48df-aa11-37ee3d62177d.png" />
D、<img width="20" height="37" src="http://admintk.100xuexi.com/UpLoadImage/2016-08-19/5843f6ac-4562-4a7b-b94f-38a9571c5f33.png" />