The cost baseline has all of the following characteristics EXCEPT:

A) It is a time-phased budget that will be used to measure and monitor cost performance on the project.
B) It shows the actual cost expenditures throughout the life of the project.
C) It is developed by summing estimated costs by period.
D) It is usually displayed in the form of an S-curve.

三视图投影规律是长相等，高平齐，宽对正。