PLEASE HELP

Which of the following most accurately describes the relationship between the interest expense on a fixed-rate mortgage and the reduction of principal amount on the mortgage? Assume a fixed installment payment.

There is a direct relationship; as the interest expense decreases, the reduction of principal amount decreases.

There is an inverse relationship; as the interest expense decreases, the reduction of principal amount increases.

There is no relationship; as the interest expense decreases, the reduction of principal amount remains the same.

There is an unpredictable relationship; as the interest expense decreases, the reduction of principal amount fluctuates unpredictably.