如何在M-V-VM设计模式中最好地表示集合中的可选择项?

I'm just beginning to explore the M-V-VM design pattern while redeveloping an application and I'm running across a consistent theme where I have collections that I need my ViewModel to expose to the View which contain items which are to be selected by the user. Please note that when I say "selected" what I mean is that they are chosen in some permanent manner such as with check boxes within a grid control and not necessary highlighted like in a regular list box control. So far I have two different ideas of how this could be implemented and I want to know whether there are any thoughts about which way is the best to go about this.I'm just beginning to explore the M-V-VM design