Which of the following situations requires the use of turn signals?

The use of turn signals is crucial for communicating your intentions to other drivers and ensuring safety on the road. Notably, you must always signal before making any turn or lane change, as this practice allows other drivers to anticipate your movements and respond accordingly. Utilizing turn signals in these situations is not just about following the rules but also about contributing to the overall safety of all road users.

Though there might be points in the other choices where signaling could be considered, such as approaching a red light, it does not encompass the broader requirement of signaling before turns or lane changes. Similarly, signaling is not limited only to highway driving but should be consistently used in all driving situations. Therefore, the requirement to signal before any turn or lane change stands as the primary rule, highlighting its importance in safe driving practices.