Which of the following best describes the purpose of a thesis statement?

A thesis statement serves as the foundation of an essay by presenting the main argument or claim that the writer intends to support throughout the piece. Its primary role is to clearly convey the central idea to the reader, allowing them to understand the writer's stance and the direction the essay will take. A well-crafted thesis statement not only highlights the main argument but also sets the tone for the entire essay, guiding the reader on what to expect in terms of evidence and analysis.

The other options do not capture the essence of a thesis statement. While introducing various topics may be important in an essay, it is not the main function of the thesis statement. Outlining the structure of the writing can be a part of the overall essay, but it does not reflect the purpose of a thesis. Similarly, while the author’s personal views might inform their argument, the thesis statement itself is focused on presenting an objective claim that can be supported with reasoning and evidence rather than a subjective opinion. Therefore, option B is the most accurate description of a thesis statement's purpose.