某班数学学习小组某次测验成绩分别是63,72,70,49,66,81,53,92,69,则这组数据的极差是( ).
A:47
B:43
C:34
D:29
我国最大的天然林区是( )
It is ____ that the police have found the related evidence in solving the murder case. (报道的)
What are you doing vacation?