Because of the bad weather, my mother ____ and lay in bed. She ______ for a week.

A．has been ill; was ill

B．fell ill; has fallen ill

C．fell ill; has been ill

D．fell ill; is ill

下列各项中，不属于科学探究学习要素的一项是（）。

A.提出问题

B.设计实验

C.形成理论

D.寻求实证