Your new colleague is trying to learn more about the options for customizing attribution models. How would you accurately summarize the options for them?

Viewable view-through conversions (VTCs) give twice as much attribution credit to viewable impressions.
You can’t enable conversion modeling and viewable view-through conversions (VTCs) on the same attribution model.
You can only enable viewable view-through conversions (VTCs) on a Last Interaction attribution model.
You can use conversion modeling to help fill the gap when some conversions can’t be observed and attributed directly.