These four broad areas can be integrated and adapted to satisfy a commander's requirements in a joint operation:

I believe the answer is: political, military, infrastructure and information

Political includes political relation or affiliation from between two countries, millitary areas usually revolves around joint training to observe the skills of soldiers from different nations, infrastructure and information could play a part in joint operation if one of the army possess necessary resources to do a certain mission while the other county does not.

Political, military, infrastructure and information are four broad areas that can be integrated and adapted to satisfy a commander's requirements in a joint operation.