A project manager wants to procure some customized products that are available in identical grade and quality from multiple vendors. What should be included in the procurement package to ensure that their offers will be comparable? 项目经理想要采购一些订制产品，且可以从多个供应商处获得相同等级和质量的订制产品。若要确保他们的报价具有可比性，采购包中应包含哪些内容？ ◑A.A cost estimate of the customized products.定制产品的成本估算 ◑B.A statement of work (SOW) specifying the required attributes and metrics of requested products详细说明所需产品必须属性和测量指标的工作说明书（SOW） ◑C.The approved project scope statement, work breakdown structure (WBS), and WBS dictionary经批准的项目范围说明书，工作分解结构（WBS）和WBS词典 ◑D.The risk management plan, and reports from risk management reviews风险管理计划以及风险管理审查报告
