What exactly does `a CPU` mean in RH App Stack Subscription

Question

This may be a very lame question to ask but I need to be very sure.

In the Red Hat Application Stack subscription details they have listed the max. number of CPUs they are going to give support to.

Now my question is what exactly they are meaning from the term CPU, my choices are:

1. 1 CPU means 1 physical unit/box/socket
   i.e. 1 box containing a n-core processor is considered 1 CPU.
2. 1 CPU means 1 core of an n-core processor
   i.e. a physical box having a quad core processor means 4 CPUs.