Which of the following types of underwriting requires the underwriters to sell the entire offering to the public?

All-or-none underwriting is the type of underwriting that mandates the underwriters to sell the entire offering to the public. In this arrangement, if the underwriters cannot sell the entire amount of the securities being offered, the deal is canceled, and no securities are issued. This structure protects the issuer by ensuring that they do not receive partial proceeds, which might not meet their financial needs or objectives.

In contrast, best efforts underwriting allows the underwriters to sell as much of the offering as they can, without the obligation to sell the entire amount. If not all securities are sold, the issuer will receive the funds for the portion sold, which can result in partial funding. Firm commitment underwriting, on the other hand, involves underwriters purchasing the entire offering outright and taking on the risk of selling the securities to the public, irrespective of whether they can sell them all. A contingency offering is not a standard term typically used in this context and does not describe a type of underwriting in the same way.

Understanding these distinctions helps clarify the dynamics and obligations between issuers and underwriters in various underwriting agreements.