What are the types of vertical marketing system? A. contractual VMS B. corporate VMS C. administered VMS A. all of above?

Thanks for your invitation. My answer is all of above VMS.

Thanks for invitation, 

I do believe that the correct answer is "4".

Thanks for the invitation. My answer is all of these options are correct.

Thanks for invitation

All the above A, B,and  C

_________Answer VMS

___________Thanks for invitation

My answer is for option (4)

all of the above is the correct answer

In my opinion it is B - Corporate VMS is more appropriate.

Thanks 

It is option D......