Over the past 20 years, skiing has become a relatively safe sport due to improvements in ski equipment. There has been a 50 percent drop in the number of ski injuries over the last 20 years. Clearly, however, there have not been decreases in the number of injuries in all categories, as statistical data readily show, for although broken legs and ankle injuries have decreased by an astounding 90 percent, knee injuries now represent 16 percent of all ski injuries, up significantly from the 11 percent of 20 years ago. The reasoning in the argument is flawed because the argument does which one of the following? ['It fails to allow for there being ski injuries other than broken legs, ankle injuries, and knee injuries.', 'It proceeds as though there could be a greater decrease in injuries in each category on injury than there is in injuries overall.', 'It assumes that an increase in the proportion of knee injuries rules out a decrease in the number of knee injuries.', 'It ignores the possibility that the number of skiers has increased over the past 20 years.']