A .低潮潮高+潮差×[1+cos(t/T×180°)]/2
B .高潮潮高+潮差×[1-cos(t/T×180°)]/2
C .高潮潮高-潮差×[1+cos(t/T×180°)]/2
D .低潮潮高+潮差×[1-cos(t/T×180°)]/2