---Cathy seems to be very happy.

---Surely she is. Having passed all the tests, she felt a great weight       off her mind.

A．taking

B．taken

C．take

D．to be taken

如果需求的增加和供给的减少同时发生，则（）

A.均衡价格和均衡数量均上升

B.均衡价格和均衡数量均下降

C.均衡价格上升，均衡数量的变化无法确定

D.均衡价格下降，均衡数量的变化无法确定

E.均衡价格和均衡数量均无法确定