We already know that we have to add every component to the app.module.shared.ts file's import list and declarations array, so we won't explain how to do it again; let's just do it as we already did a number of other times.
While we're there, let's add the missing routes as well to the RouterModule, just after the quiz ones:
[...]
{ path: 'quiz/create', component: QuizEditComponent },
{ path: 'quiz/edit/:id', component: QuizEditComponent },
{ path: 'quiz/:id', component: QuizComponent },
{ path: 'question/create/:id', component: QuestionEditComponent },
{ path: 'question/edit/:id', component: QuestionEditComponent },
{ path: 'about', component: AboutComponent },
[...]
We can easily note a big difference between the quiz/create and the question/create/:id routes--the latter will require an :id parameter, just like the question/edit/:id counterpart. We already explained the reason earlier, but it can't hurt to repeat it here--the Create mode will need to know the QuizId when issuing the Put Http call to the QuestionController, as it's a required property of the Question Entity.