Your answer is: A) Purchasing power
In order to spend money, you need purchasing power. Purchasing power means someone can purchase something like a product or service. Having confidence doesn't mean you can buy something. Well, having confidence is helpful when to comes to buying, but that doesn't make it legal for you. Less disposable income will lead to purchasing power. you need to give something up in order to get something. That's the way it works.
Best Of Luck,