Which of the following is true about the project life cycle?

以下哪个关于项目生命周期的说法是正确的?

A.The project life cycle of all projects includes five stages: start-up, planning, implementation, monitoring and closing

A. 所有项目的项目生命周期都包括启动、规划、执行、监控和收尾等5个阶段

B. The responsibilities and roles of relevant parties usually remain unchanged throughout the project life cycle

B. 相关方的职责和作用，在整个项目生命周期中通常保持不变

C. Under the premise of not significantly affecting the cost, the ability to change the final characteristics of project products is the largest at the beginning, and weakens with the progress

C. 在不显著影响成本的前提下，改变项目产品的最终特性的能力在开始时最大，随着进展而减弱

D. The change of manpower and cost is the same in all projects, the biggest at the beginning

D. 人力和成本的变化在所有的项目中都是一样的，开始时最大