如图，用纸片把盛满水的杯子的杯口盖住，再使杯口向下，水也不会流出来，主要是因为：

A、纸片很轻

B、水粘住纸片

C、空气有浮力

D、大气对纸片有向上的压力

—The pet dog in your hand is very nice. Is it （）.
—Yes, but I'll give it to my friend, Lucy, as （）birthday present.

A. you; her

B. yours; hers

C. yours; her

D. you; hers