Final answer:
Securitizing is the process by which lenders swap mortgage loans for mortgage-backed securities to off-load risk to investors, which played a role in the 2008-2009 financial crisis.
Step-by-step explanation:
When lenders swap mortgage loans for mortgage-backed securities (MBS), the process is known as securitizing. In this process, lenders sell their mortgage loans to financial companies, which then pool these mortgages to create a financial security that is sold to investors. This way, lenders can offload the risks associated with mortgage loans to the investors. These MBSs offer investors the potential for a steady stream of income, based on the repayment of the underlying mortgages. However, excessive securitization without proper risk assessment was one of the contributing factors to the 2008-2009 financial crisis.