每天都会有新的盐分进人海水，海水中也会有一些盐分进入海床沉积层。新注入的盐分数量与海水里跑

掉的盐分数量互相抵消，海水的平均溶盐浓度保持稳定。这表明[ ]

①量变是质变的必要准备

②质变是量变的必然结果

③静止是一种特殊的运动

④物质是运动的物质

A、①②

B、③④

C、②③

D、①④

—How do you like the concert given by the "Foxy ladies"?      

—Exciting, _____ one piece of the music wasn't played quiet well .      [ ]

A. so

B. though

C. because

D. and