The Primary Reason That New Corporate Bond Issues Typically Have

The primary reason that new corporate bond issues typically have a credit rating of BBB or better is that

A) the SEC will not approve a new bond issue that is below investment grade.
B) reputable investment banks refuse to underwrite junk bond issues.
C) there is no demand in the public markets for bonds that are below investment grade.
D) it is usually cheaper for smaller firms to borrow from commercial banks than to tap the public market.