What is a context which allows MemberwiseClone() to be called

I have a Person class and a ocPeople class defined as:

ocPeople = ObservableCollection(Of Person)

ocPeople is used as the ItemsSource for a ComboBox. What I want to do is to create another ObservableCollection(Of Person) which is the original with the Person selected in the ComboBox removed. Here is how I do that:

Private Sub cbxPeople_SelectionChanged(sender As Object, e As SelectionChangedEventArgs) Handles cbxPeople.SelectionChanged
	CurrentPerson = CType(cbxPeople.SelectedItem, Person)
	Dim oc As ObservableCollection(Of Person) = CType(ocPeople.MemberwiseClone(), ObservableCollection(Of Person))
	oc.Remove(CurrentPerson)
End Sub

This yields an error:

'Object.Protected Overloads Function MemberwiseClone() As Object' is not accessible in this context because it is 'Protected'.

What context would allow MemberwiseClone() to be called? If MemberwiseClone() is not used, what is the best way to create a new ObservableCollection with just one member removed?