How would paying workers higher wages, which would afford them "greater leisure time," lead them to spend more money, thereby profiting society as a whole?

Paying workers higher wages would cause them to spend more money, because they will most likely feel more obligated to buy more things because they have the money to do so. So it would profit society as a whole, because that would mean, people are buying more, because of being payed more, and then people work more, and what is being bought will be made more of which is the product of working more to get paid more so that would restart the whole cycle.

Hope that helped :)

the answer is definitley b!