in reply to When another intelligent species appears on Earth, humanity shall
If we're talking about another species, i would think the humans would be there creators, and hence treat them like second-class citizens, much like they deny but do in the Star Trek universe.
Assuming you mean extra-terrestrial race, well, it is likely all the emotions will follow suit until whatever happens happens. That's simply an unpredictable relationship. For that, i would have added an option of "Cautiously try to treat them as equals."