the correlation between cell phone usage and life expectancy is very high. should we buy cell phones to live longer?

A.) yes. the correlation indicates that cell phones may contain some mechanism by which people become healthier. Although further research into the mechanism is required, cell phones should be subsidized in order to increase public health.

B.) No. Cell phones are expensive, and there are alternative treatments that may increase life expectancy more consistently. The existence of a strong relationship between ownership of a cell phone and life expectancy does not imply that cell phones should be subsidized.

C.) Yes. Cell phones give people more control over their lives and make is possible for them to achieve a high standard of living, which increases life expectancy, therefore, cell phones should should be subsidized in order to increase public health.

D.) No. Cell phones are easier to obtain for people who are relatively wealthy, and those who are wealthy typically have higher life expectancy. Since there is a lurking variable in the model, cell phones not be subsidized.