Answer:
b. mortgage backed securities diversify credit risk for the investor.
Step-by-step explanation:
An investor, such as a bank, may prefer to invest in securities backed by a pool of mortgages purchased in the secondary market rather than in an equal dollar amount of mortgage loans because mortgage backed securities diversify credit risk for the investor.
In Mortgage Backed Securities, credit risk is diversified as there are many borrowers and investors between whom credit risk diversifies. So that makes investor such as bank prefer the option.