单项选择题
Maintenance activities include(). ① making enhancements to software products ② developing a new software product ③ correcting problems ④ adapting products to new environments
A.①② B.①③④ C.②③④ D.①②③④
A.①② B.②③ C.③④ D.①②③④
A.向承建单位发“停工令” B.有权自行改正后通知承建单位 C.应当报告建设单位后自行改正 D.应当报告建设单位要求承建单位改正