In 1997, 10% of automobile insurance premiums went to pay costs arising from injuries occurred in car accidents, In 2007, cost rose despite the fact that cars were much safer in 2007 than in 1997. Which of the following, if true, best explains the discrepancy outlined above?
A. Fewer accidents occurred in 2007 than in 1997.
B. In 2007, people drove more slowly than in 1997.
C. Medical costs rose sharply between 1997 and 2007.
D. Repairing costs of cars grew more over the period.
