A：印度洋沿岸
B：红海沿岸
C：非洲东海岸
D：地中海沿岸
从食品店购买的蔗糖配成溶液，做银镜反应实验，往往能得到银镜。产生这一现象的原因是( )
—How do I improve my math grades?
—_______, you should listen to the teacher carefully.
