What is default settings to reffer to file location in xcode project?

What is default settings to reffer to file location in xcode project ?

i have doubts between them

1. relative to build project
2. relative to project
3. relative to enclosing group
4. relative to source path
5. Absolute path

This doesn't seem to be well documented. As I read "How Files are Referenced" in the "Xcode Project Management Guide":

1. If the file is in the project's folder, you get a reference relative to an enclosing group.
2. If the file is created by one of the targets, you get a reference relative to the build product.
3. Otherwise, I think, you get an absolute path.

By default - Eclosing-Group*.

*Beginning Xcode (James Bucanek) Chapter 5, p.76