Not managing your wisely can result in

D. A decrease in your credit score

Explanation:

Not managing one's debt wisely can result in  a decrease in that person's credit score. The role of a credit score is to show how likely or unlikely a person can repay their loans or debts. It is a three digit number ranging from 300 to 850. The higher your score is the better you are at managing your debts and vice versa. According to FICO reports , most people's scores range between 600 to 750. 800 and above is considered excellent.