Final answer:
The formality of a discussion is determined by the topic, audience, and purpose. These factors guide the tone, language, and structure appropriate for the situation.
Step-by-step explanation:
The three factors that determine the formality of a discussion are: topic, audience, and purpose. These elements work collaboratively to shape how formal or informal a discussion will be. The topic of the discussion often sets the initial tone, as some subjects are inherently more formal than others. Understanding the audience is crucial as it influences the language, tone, and level of detail needed. Their expectations, background knowledge, and cultural context are determining factors. Additionally, the purpose of the conversation or written piece helps to establish the appropriate level of formality. Whether it is to inform, persuade, entertain, or a combination of these, purpose drives the structure and presentation of ideas.
It's valuable to discuss with peers and instructors to clarify aspects such as purpose, audience, genre, or culture. Moreover, when writing proposals and research arguments, distinguishing between facts, inferences, and opinions is key since this can affect the strength and perception of the argument. Adjusting format, tone, language, and conventions to meet specific audience needs is a part of the writing process. Hence, the correct answer to the question is: B. Topic, audience, and purpose.