【单选题】Which of the following are important ways in which mortgage markets differ from the stock and bond markets?
A.
The usual borrowers in the capital markets are government entities and businesses, whereas the usual borrowers in the mortgage markets are individuals.
B.
Most mortgages are secured by real estate, whereas the majority of capital market borrowing is unsecured.
C.
Because mortgages are made for different amounts and different maturities, developing a secondary market has been more difficult.
D.
All of the above are important differences.
E.
Only A and B of the above are important differences.