Why all stars appear at the celestial equator only?

So there was this question If the stars are seen to rise perpendicular to the horizon by an observer, he is located on the:

a) Equator

b) Tropic of Cancer

c) South Pole

d) North Pole

But the answer can be either of them no? Cuz it the observer is standing at the tropic of cancer and the star's path is just above above/ parallel vertically so don't you think that can also be perpendicular?