Which of the following is NOT one of the three main types of speeches?

In public speaking, the three main types of speeches are designed to fulfill different purposes: to inform, to persuade, and to entertain. Informative speeches aim to educate the audience about a particular topic, providing them with new information or insights. Persuasive speeches seek to influence the audience's beliefs or behaviors, advocating for a particular viewpoint or action. Entertaining speeches are crafted to amuse and engage the audience, often using humor or storytelling.

Descriptive speeches, while they can be a form of informative speaking, do not represent one of the primary categories of speech types as outlined in most public speaking frameworks. Instead, they are often included under the umbrella of informative speeches when a speaker seeks to provide vivid details about a subject. Therefore, it is correct to say that "descriptive" does not fit within the main trio of identified speech types in formal public speaking education.