LSAT－6－3－7

7.Which one of the following is an assumption upon which the author's conclusion concerning helmets for horseback riders depend?

(A) Medical care for victims of horseback-riding accidents is financial drain on tax funds.

(B) The higher rate of serious head injury suffered by victims of horseback-riding accidents is due to the difference in size between horses and motorcycles.

(C) The medical costs associated with treating head injuries are higher than those for other types of injury.

(D) Most fatalities resulting from horseback-riding and motorcycle accidents could have been prevented if the victims had been wearing helmets. (E) When deciding whether to enact helmet laws for motorcyclists and horseback riders, the jurisdiction's primary concerns is the safety of its citizens.

Key is A. Why is  D wrong?

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