Which of the following best describes a mortgage?

A mortgage is best described as a loan used to purchase real estate because it specifically involves borrowing money from a lender to finance the acquisition of property. The borrower agrees to repay this loan over a specified period, usually with interest, and the property itself serves as collateral for the loan. This means that if the borrower is unable to make the mortgage payments, the lender has the right to take possession of the property through a legal process known as foreclosure.

Other options may seem relevant in the context of real estate but do not accurately define a mortgage. For instance, taxes are government-imposed charges on property ownership, not a form of financing. A rental agreement pertains to the landlord-tenant relationship that involves leasing property, rather than obtaining funds to buy it. Lastly, a record of property ownership refers to documentation of who legally owns a property and does not involve the borrowing of money. Thus, the correct answer highlights the essential purpose and function of a mortgage in real estate transactions.