In Order for a Project to Generate a Positive Net

In order for a project to generate a positive net working capital cash flow at the end of its useful life,

A) the project must have generated a cumulative negative cash flow during the life of the project.
B) the project must have generated a cumulative positive cash flow during the life of the project.
C) the project must have generated a cumulative negative cash flow at the conclusion of the project.
D) the project could not have generated a positive cash flow at the opening of the project.