I'll give you a question, please answer with step-by-step reasoning process.
The lights were used for a safe landing, so where were they installed?\nOptions:\n- building\n- turned at night\n- road\n- carnival\n- plane

plane
Plane is an aeroplane or is a powered flying vehicle with fixed wings and a weight greater than that of the air it displaces.

The lights were used for a safe landing, so they were installed in plane.

.

Final answer: plane