Every individual is continually exerting himself to find out the most advantageous employment for whatever capital he can command. It is his own advantage, indeed, and not that of the society, which he has in view. But the study of his own advantage naturally . . . leads him to prefer that employment which is most advantageous to the society. –The Wealth of Nations,
Adam Smith

According to the passage, how do people pursuing self-interest benefit society?

People will naturally take jobs where they can reform society.
People will seek out the highest-paying jobs, and these benefit society most
People pursuing capital will always start new businesses, thus benefitting society.
People will find employment only if they are good workers, which benefits society.