The simple facts are these: the number of people killed each year by g...
A. Most incidents involving grizzly bears are fatal. This option suggests that the majority of incidents involving grizzly bears result in fatalities. However, the passage does not provide information or make claims about the fatality rate of incidents involving grizzly bears. Therefore, this option is not the assumption the author relies upon.
B. Grizzly bears are no longer the danger they once were. This option implies that grizzly bears are less dangerous now compared to the past. However, the passage does not discuss any changes in the danger level of grizzly bears over time. Therefore, this option is not the assumption the author relies upon.
C. The number of fatalities per year is an adequate indication of something's dangerousness. This option aligns with the argument made in the passage. The passage compares the number of fatalities caused by different entities (grizzly bears, lightning on golf courses, and electric blenders) to suggest that they are all similarly dangerous. This comparison relies on the assumption that the number of fatalities per year is a suitable indicator of something's dangerousness. If this assumption were false, and the number of fatalities alone was not sufficient to determine dangerousness, it would weaken the argument's conclusion. Therefore, this is the assumption the author relies upon.
D. A golf course is a particularly dangerous place to be in a thunderstorm. This option focuses on the danger of being on a golf course during a thunderstorm. However, the passage does not directly address the danger level of golf courses during thunderstorms or make any specific claims about the danger of being on a golf course in such conditions. Therefore, this option is not the assumption the author relies upon.
E. Something is dangerous only if it results in death in the majority of cases. This option suggests that something can be considered dangerous only if it results in death in the majority of cases. The passage does not explicitly state or imply this condition for determining dangerousness. Instead, it compares the number of fatalities caused by different entities to argue for their similar levels of danger. Therefore, this option is not the assumption the author relies upon.
In summary, option C is the assumption the author relies upon, which is that the number of fatalities per year is an adequate indication of something's dangerousness.