People older than 60 are ______ times less susceptible to radiation-induced fatal cancers than those in the average population.

The correct response indicates that people older than 60 are 3 to 10 times less susceptible to radiation-induced fatal cancers than the average population. This statistic reflects the biological differences in susceptibility to radiation between younger and older individuals.

As people age, their cells typically undergo various biological changes, and the cumulative effects of previous exposures to radiation and other risk factors can influence their overall cancer risk. The data suggests that older individuals may have lower susceptibility to developing radiation-induced cancers, which can be attributed to several factors, including the slower rate of cell division in older adults, which may diminish the likelihood of mutations that could lead to cancer as a result of radiation exposure.

While other options present higher multipliers, the lower range of 3 to 10 is supported by existing epidemiological data, which indicates that the relationship is more nuanced and may not be as extreme as suggested by the other options. This underlines the importance of distinguishing between risk factors and understanding how age-related biological processes can affect susceptibility to cancer in the context of radiation exposure.