Final answer:
A thesis statement is a concise summary of the main point or claim of an essay or research paper and it typically presents the topic and the writer's position on that topic.
Step-by-step explanation:
A thesis statement is a concise summary of the main point or claim of an essay or research paper. It is typically one sentence that presents the topic and the writer's position on that topic. The four options provided are all functions of a thesis statement, but the correct answer is option a. 'asks a question' because a thesis statement makes a declarative statement rather than asking a question.
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