Which of these statements is true about the relationship between literacy rates and standard of living?

when one social condition rises, the other usually falls. literacy rates are negatively correlated with standard of living.

when one social condition rises or falls, so does the other. literacy rates are positively correlated with standard of living.

the two social conditions are not correlated by any given pattern. literacy rates have no correlation with the standard of living.

the correlation between literacy and standard of living is most prominent in farm-based economies.