Which type of Money Market Security is least likely to be backed by the federal government?

Commercial paper is a short-term unsecured promissory note issued by corporations to finance their short-term liabilities. Unlike Treasury bills, which are direct obligations of the federal government and backed by its full faith and credit, commercial paper does not have any government backing. This makes it inherently riskier compared to other money market securities that are explicitly backed by government guarantees.

Treasury bills are backed by the federal government and are considered one of the safest investments available. Negotiable certificates of deposit (CDs) are also relatively secure, as they are typically issued by banks and may be insured by the Federal Deposit Insurance Corporation (FDIC) up to certain limits. Repurchase agreements, while typically involving private parties, often include treasury securities as collateral, which adds a layer of security.

In summary, commercial paper stands out in this context as it is issued by corporations and does not carry any federal backing, thereby making it the least likely among the options provided to be associated with government guarantees.