A、<img width="21" height="41" src="http://admintk.100xuexi.com/UpLoadImage/2016-08-19/2dcd6e40-1972-4873-ba3d-256edfe37651.png" />
B、<img width="23" height="41" src="http://admintk.100xuexi.com/UpLoadImage/2016-08-19/76e421f8-4e7c-4320-9dce-dd3f27f2f796.png" />
C、<img width="24" height="41" src="http://admintk.100xuexi.com/UpLoadImage/2016-08-19/c16aeb6b-c3f5-4a2f-8052-3b3af7aaddf9.png" />
D、<img width="21" height="41" src="http://admintk.100xuexi.com/UpLoadImage/2016-08-19/e802ef64-b099-4732-8d3b-647846f4b394.png" />