Which statement is true about function libraries in QuickTest Professional?

A.
If you define a VBScript class, it can be called only within the QuickTest Professional action or
function library in which you defined it

B.
You can use the RegisterFunc statement to register a user-defined function that will override an
existing test object method

C.
By default, steps that use user-defined functions are included in the run results after a run
session.

D.
If another user modifies a function library thatis referenced by a test, or ifyou modify the
function library using an external editor, the changes will take effect automatically

Explanation:
Reference:http://www.qtp10.com/2009/06/registeruserfunc-statement-in-qtp.html