Answer:
The answer to the question: Between the years 2009 and 2013, the primary factor that caused collisions in California:____, would be: Speeding.
Step-by-step explanation:
According to the statistics from those years, in the state of California the leading reasons for car crashes, both mild and severe, were: distraction while driving, driving while being impaired and the most important of all was speeding. Another reason that was given was distracted driving and finally driving while having consumed alcohol. This data comes from California´s highway patrol data, that show that in 2013, alone, more than 150 thousand crashes, both fatal and non-fatal, happened due primarily to speeding, followed by the other reasons.