题目

如图，有一张地图上有五个国家，现在要用四种颜色对这一幅地图进行染色，使相邻的国家所染的颜色不同，不相邻的国家的颜色可以相同．那么一共可以有多少种染色方法？ 答案：解：4×3×2×2×2=96（种）答：一共可以有96种染色方法。In the old society, we were ________, but now we are the master of the factory. [　　] A．looked forB．looked after C．looked onD．looked down upon