一列沿着x轴正方向传播的横波，在t=0s时刻的波形如图甲所示，则图乙表示图甲中E、F、G、H四个质点中哪一个质点的振动图象（　　）

A．E点

B．F点

C．G点

D．H点

II. Choose the correct answers after reading the passage.

1.    What did the group do first in the morning? They           .

A．went into the forest slowly

B．left the chimp family sleeping in a tree

C．observed the family of chimps wake up

D．helped people understand the behaviour the chimps