Final answer:
The correct answer is D) APR. APR stands for Annual Percentage Rate, which is a measure of the cost of borrowing money.
Step-by-step explanation:
The correct answer is D) APR. APR stands for Annual Percentage Rate, which is a measure of the cost of borrowing money. The other options, A) PMT, B) PPMT, and C) NPD, are all financial functions commonly used in finance and accounting.