What happens when you click Run Form Debug in Forms Builder?

What happens when you click Run Form Debug in Forms Builder?

A.
The forms run on your local machine using a debug executable client.

B.
The forms runs a three-tier environment using the application server URL that you specify in runtime preferences.

C.
The form runs in a three-tier environment using the application server URL that you specify in debug preferences.

D.
The form runs in a simulated three-tier environment using an applet viewer that is included with the product to enable debugging.