It's Technically Possible for One Business Object to Call Another

It's technically possible for one business object to call another. Outside of using utility objects are any of the following valid reasons why you would want to do this?

A) No. objects should never call other objects.
B) Yes but object calling other objects could lead to undesirable memory problems so care must be taken.
C) Yes, to create a wrapper object as a vehicle for a reusable sequence of application logic.
D) Yes, but only if the object is calling itself.