He felt his chair ___ at the time of the earthquake.

A．moved

B．to move

C．is moving

D．moving

当变量X的数值增大时，Y变量的数值也显著增大，坐标点的分布呈窄带状，称为( )

A．强正相关

B．弱正相关

C．强负相关

D．弱负相关