The Relationship Between More Education and Higher Levels of Happiness

The relationship between more education and higher levels of happiness probably results from the fact that

A) more education makes you more competent and therefore happier.
B) more education leads to more satisfying and financially rewarding jobs.
C) intelligence is related to happiness and more education requires more intelligence.
D) more education means you are more self-aware, more in tune with the big picture of life, and more likely to sacrifice short-term rewards for long- term gains.