The situation that best illustrates a violation of the rule of law is option D, which states that the president is free to ignore laws he doesn't agree with because he's powerful.
That situation goes against the republican democratic principles of the United States of America, where the Constitution guarantees the division of powers, so the President must respect the laws passed by Congress and apply them, like it or not.
If the president applied the laws at his will, we would be in the presence of a non-democratic or republican system, but rather an autocratic system that concentrates power in a single figure whose actions and decisions are not subject to external legal restrictions or mechanisms of popular control, as are dictatorships and absolute monarchies.