问题
单项选择题
Each box is an activity; the number it contains is the duration of the activity in days.The duration of the critical path is （）.
A．16days
B．14days
C．19days
D．20days
答案
参考答案：C
解析：
[分析]： 关键路径为最长时间的线路，3+6+7+1+2=19。