References
In the following descriptions, the forward slash (/) is used. This applies to macOS; Windows uses the backward slash (\).
File
This entry will display the path name present in the Reference field of the selected XRef object. It can display a single name ("XRef.c4d"), an absolute path ("C:/myFolder/XRef.c4d") or a relative path ("./myFolder/XRef.c4d"), depending on the way the file has been referenced.
This entry displays the absolute path of a file when resolved automatically from a relative path. For example, if the name of your XRef object (the one found in the Reference link of an XRef object, when selected in the Object Manager) is "./myFolder/XRef.c4d" and your referenced scene can be physically found in a "myFolder" folder at the same level as the master scene, on the C:/ drive, the resolved path will be: "C:/myFolder/XRef.c4d". This is the exact location where this file has been found. Very useful if you notice that you are not getting the proper referenced scene when loading/refreshing an XRef from a relative path, this allows you to check the full absolute path as resolved by Cinema 4D.
This entry shows the namespace used for the selected XRef object.
The objects list will show the content of each XRef object, along with materials and dependencies (dependencies are XRefs within another XRef). This list gives you at a glance all the XRef objects contained in the scene, for quick editing.