When towed by a powerboat, waterskiing and other tow-sports must only take place during what hours in Virginia?

Towed sports such as waterskiing in Virginia are regulated to occur during specific hours to promote safety and visibility. The correct choice indicates that these activities can take place from half an hour before sunrise to half an hour after sunset. This timeframe is designed to maximize daylight, providing better visibility for both the skier and the boat operator, and reducing the risks associated with decreased visibility during early morning or evening hours.

By allowing these activities only during this set period, the regulations help ensure that participants have the best possible conditions for safe enjoyment, as twilight can obscure visibility and make it difficult to see other boats or obstacles in the water. The other options do not align with this regulation. For instance, allowing all daylight hours could extend activities into times when visibility may still be compromised, while designating an evening-only timeframe would limit participation and contradict the intention of maximizing safety during optimal lighting conditions.