Final answer:
Neptune is a few light hours away from the Sun, with light taking approximately 4.1 hours to travel this distance, making option C the correct answer.
Step-by-step explanation:
The distance from the Sun to Neptune is not measured in light seconds or light years because those are either too short or too long. According to astronomical data, it takes light approximately 4.1 hours to travel from the Sun to Neptune.
Since a light hour is the distance light travels in one hour, Neptune is a few light hours away from the Sun, not light seconds, weeks, days, or years. Therefore, the correct answer to how far Neptune is from the Sun is C) A few light hours.