Final answer:
The Army value described by putting the welfare of others before one's own is Selfless Service. In international law, state sovereignty is a fundamental principle. A foreign policy based on mutual respect involves support when necessary without needless interference.
Step-by-step explanation:
The statement "Put the welfare of the nation, the Army, and your subordinates before your own" best describes the Army value of c) Selfless Service. This value is about putting the needs of others before your personal needs or interests, a commitment that is integral to military service and leadership.
Regarding the piece of information about international law, the correct answer would be a. state sovereignty. International law is largely based on the principle that states are sovereign and have supreme authority within their own territories.
As for the approach described as mutual respect, in terms of being available to support others when called upon, but not interfering unnecessarily in their affairs, it can be associated with a foreign policy that emphasizes d. mutual respect rather than aggressive interventionism or isolationism.