The City of Sweet Pea had outstanding $$5$ million of $6$ percent bonds with a call provision. Due to changes in the prevailing interest rates, the city issued new bonds at $4\mathrm{.}5$ percent and used the proceeds to call the $6$ percent bonds. This is an example of

Group of answer choices

Debt retirement.

Debt refunding.

In$-$substance defeasance.

Financial mismanagement.