---Alice, you look puzzled, Have you understood it?

---Yes．I _____another problem just now．

A．l have thought of

B．am thinking of

C．had thought of

D．was thinking of

当风速一定时，水平地转偏向力的大小为（）。

A．低纬大于高纬

B．低纬小于高纬

C．低纬等于高纬

D．与纬度无关