Beginning in the $1980\text{'}$s$,$ a large part of corporate borrowing has taken place in the form of "low grade' or 'junk' bonds. If these bonds are rated at all, they are rated below:

A$)$ investment grade

B$)$ BBB$-$ by $58.P$

C$)$ Baa$-$ by Moody's

D$)$ all of the above

As discussed in class the U$.$S$.$ total national debt $($gross debt$)$ is approximately $$33\mathrm{.}0$ trillion plus. Further, in Fiscal Year $2023(10/1/22$ through $9/30/23)$ the U$.$S$.$ government ran a deficit of approximately $$1\mathrm{.}7$ trillion. Credit rating agencies such as Fitch, Moody's, and Standard and Poor's $($S