Final answer:
Low tax and interest rates are economic factors that contribute to societal stability by fostering conditions like business investment and consistent economic growth.
Step-by-step explanation:
Among the choices provided as an economic factor that contributes to the stability of a society, low tax and interest rates can be considered favorable. Low taxes and interest rates can lead to increased investment by businesses, which can support consistent economic growth, maintain low and stable unemployment rates, and keep prices consistent. Other options, such as fluctuating prices or a strong military, may not directly contribute to economic stability, as fluctuating prices can lead to uncertainty and a strong military does not inherently relate to economic conditions.