If you see a red navigation light of another aircraft out to the left at night, what does it indicate?

When you see a red navigation light on another aircraft positioned to your left at night, this indicates that the other aircraft is approaching from your left side. The red light is typically on the left wing of an aircraft, which means that you are seeing it because the aircraft is flying towards you.

Given this context, the correct interpretation about the aircraft's position and trajectory is that you should be cautious about the potential for a collision, rather than assuming you are safe from it. The presence of the red light generally signifies that the aircraft is on a collision course unless you take steps to alter your flight path to maintain separation. Therefore, it highlights the importance of the navigation light system in assessing the relative positions and movements of aircraft at night.

Other options suggest a false sense of security or misinterpret the situation, as an aircraft with a red light on the left is clearly an indication of an approaching aircraft, not one that is safely distant or moving away.