People are most likely to be obedient to rules a. are set up by people in authority. b. requires personal effort and interest. c. benefit the common good of others. d. benefit only themselves.

I would like to believe that people are most likely to be obedient to rules that benefit the common good of others (C).

Sadly, I don't.

Perhaps I've become cynical because of my age.  But, without seeing any psychological analysis or survey data on the subject, my opinion is that people are more likely to be obedient to rules that benefit only themselves (D).

current and voltage can both be different in different parts of a circuit so it matters where you place the ammeter and voltmete