无码高清视频|成人自拍视频|欧美成人午夜无码A片秀色直播|草美女视频网站|美女被操网站在线观看

單項選擇題

The use of sinking and dispersing agents for the removal of surface oil is ().

A.the most common method used in the United States
B.too expensive for common use
C.generally safe to sea life
D.generally harmful to sea life

微信掃碼免費搜題