A company is developing a new product. During the testing stage, customers identify a serious defect with it.What should the project manager use to determine an appropriate solution? 公司正在开发一些新产品，在测试阶段，客户发现该产品的一个严重缺陷。项目经理应该使用什么来确定合适的解决方案？ ◑A.Cause-and-effect diagram因果图 ◑B.Six Sigma六西格玛 ◑C.Expert judgment专家判断 ◑D.Design for X面向X的设计
