Fast driving is particularly dangerous in which of the following situations?

Fast driving is particularly dangerous in all of the situations mentioned because each of them presents unique challenges that can significantly increase the risk of an accident.

In heavy rain, reduced traction on the road can lead to hydroplaning, where the tires lose contact with the surface of the road, making it difficult to steer or stop effectively. The visibility is often also reduced during rain, which means that a driver needs more time to react to potential hazards.

On narrow roads, the limited space can make it challenging to maneuver safely, especially at higher speeds. Sharp turns, oncoming traffic, and obstacles can all come into play much quicker, leaving little room for error.

Heavy traffic inherently results in a greater number of vehicles close together, which means that the chances of needing to stop or slow down increase. Speeding in these conditions can reduce reaction times and escalate the severity of potential collisions.

Thus, the combination of these factors makes fast driving particularly hazardous in each scenario, and it's essential to adjust driving speed accordingly to maintain safety.