题干
The conference has been held to discuss the effects of tourism _____ the wildlife in the area.
A：o
B：i
C：at
D：with
答案(点此获取答案解析）
B
A：o
B：i
C：at
D：with
和
时，紧急刹车时的刹车痕与刹车前车速的关系曲线，则