The clause in the mortgage agreement that allows a lender to call the entire balance of the loan due prior to its maturity is the...

The clause in a mortgage agreement that allows a lender to demand the full repayment of the loan balance before its scheduled maturity is known as the acceleration clause. This clause provides the lender with a means of protecting their financial interests, particularly if the borrower fails to meet the terms of the loan, such as missing payments or defaulting on the agreement.

When an acceleration clause is invoked, it effectively accelerates the timeline of payment, making the total amount due immediately. This is vital for lenders as it minimizes their risk exposure in scenarios where the borrower's financial situation deteriorates.

In contrast, the other options serve different purposes within a mortgage agreement. The habendum clause defines the extent of ownership rights being conveyed. The prepayment clause pertains to the conditions under which a borrower can pay off the loan early, usually mentioning whether there are penalties for doing so. The defeasance clause is related to releasing a borrower from a mortgage obligation once the loan has been paid off. Each of these clauses has distinct legal implications that do not pertain to the lender’s right to accelerate loan repayment due to a default.