Is a specific thing, person, or event that demonstrates a point.
a topic sentence
a fact
a statistic
an example

D). An example.

Explanation:

As per the question, an example is described as a specific thing, person, or event that illustrates a point. Examples not only function to demonstrate a point in order to substantiate a claim but also to enhance the readers' understanding and clarify the term, concept, or process. It also serves to explain a general rule and validate its claim. Therefore, option D is the correct answer as 'examples' or 'illustrations' to establish a point regarding a particular event, process, or person that would assist the readers to understand it effectively as it offers a clear and comprehensive meaning to them.

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