Testing combination of methods when every component method is already tested

Consider the example below:

void Whole()
{
   A().B().C();
}

I've already written test methods for A, B, C. These are used in many different possible ways, for example A().C().B() or B().A().C() or B().C().A(). One of them is used in Whole method. There are 3! combination when all of them corporate in.

Question: is there any necessity to write test for any used combination such as what Whole uses?