Subprime mortgages expanded to about 35% of all mortgages issued in the United States in 2004. Which of the following could have decreasedthe growth of these mortgages?Check all that apply.

(a) The Federal Reserve setting low interest rates in the early part of the 2000s

(b) The phasing-out of financial instruments that allowed for securitization of subprime mortgages

(c)Banks maintaining traditional levels of leverage

(d) A shift to lower-risk investments by investors