How do I structure inheriting Flutter widgets?

Question

For instance, if I had two types of widget for handling questions that both extend some generic class:

class MultiChoiceQuestion extends GenericQuestion
{ MultiChoiceQuestion(MultiChoiceModel model) : super(model)
}
class UserInputQuestion extends GenericQuestion 
{ UserInputQuestion(UserInputModel model) : super(model)
}
class GenericQuestion extends StatefulWidget {
GenericQuestion(GenericModel)
}

And wanted to pass a list of questions to some parent class LessonWidget:

class LessonWidget extends
StatefulWidget {
  LessonWidget(List<GenericQuestionModel> questions)
}

I run into the issue of not being able to create the question widget in place (as I cannot be sure whether to call to a MultiChoice or UserInput constructor).

I believe this is a fault of my structure. I am trying to implement a form of MVC. How best should this be structured?

i.e What should the LessonWidget build method look like?