Req uiremen t s for which relation s hips to ot her req uiremen t s , solu tion com ponen ts, or releases, p h ases, or iteration s a re establis hed.
选项：

A:Req uiremen t s(traced)
B:Modelling notation s / s t a n dards
C:Req uiremen t s life cycle m a n agemen t tools
D:Modelling tools