Final answer:
Hormonal differences between men and women, influenced by varying levels of estrogen and testosterone, contribute to the disparities in life expectancies.
Step-by-step explanation:
The biological component that might explain the difference in life expectancies between men and women is A. Hormonal differences. In biological terms, hormones play a critical role in the functioning and development of the human body, and they differ between the sexes. The varying levels of sex hormones such as estrogen and testosterone are hypothesized to contribute to longevity differences. For example, estrogen has been linked to protective effects on the heart, which might partly explain why women often live longer than men. Additionally, hormonal influences may predispose men to engage in riskier behaviors, contributing to a shorter average lifespan.