单项选择题
The drift and set of tidal，river，and ocean currents refer to the（）.
A.position and area of the current B.speed and direction toward which the current flows C.type and characteristic of the current's flow D.None of the above
单项选择题 The direction of the surface wind is（）.
单项选择题 The direction of the southeast trade winds is a result of the（）.
单项选择题 The currents are（）mosoonal origin．
