Answer:
The correct answer is "knowing what you spend B
Explanation:
By using cash intead of credit card to purchase is way easier to know how much you spend. This is simple to see, in the literally meaning, because when you use cash you actually have it in your hands and know before hand the amount of what is left after spending. Instead, while using credit card, you just swipe it and you buy whatever, what makes easy to lose the track of how much do you spend.