What is the most common cause of car-bicycle crashes involving motorists?

The most common cause of car-bicycle crashes involving motorists is when motorists turn left in front of oncoming bicycle traffic. This type of crash often occurs because drivers may not be vigilant about checking for cyclists before making a turn. Bicycles can be less visible than other vehicles, especially at intersections where a motorist's line of sight may be obstructed. When a driver turns left without looking for oncoming bicycles, they may misjudge the speed of the approaching cyclist or fail to see them altogether, leading to potentially serious collisions. This situation highlights the importance of careful observation and yielding to all traffic, including bicycles, at intersections to ensure the safety of all road users.

The other options describe situations that can cause accidents but are statistically less common compared to the scenario of turning left in front of cyclists. For instance, speeding in residential areas, while dangerous, doesn't directly correlate with the specific dynamics of left-turning maneuvers involving bicycles. Distracted driving due to texting is a serious concern but tends to be a contributing factor across a broader range of accidents rather than being specific to bicycle crashes. Similarly, ignoring traffic signals poses risks in general but may not specifically lead to the most frequent bicycle-related incidents. Understanding the unique risks involved when navigating