Final answer:
The purpose of the topic sentence in an effective compare and contrast paragraph is to introduce the thesis.
Step-by-step explanation:
In an effective compare and contrast paragraph, the purpose of the topic sentence is to introduce the thesis. The topic sentence states the main idea that will be discussed in the paragraph. It provides a clear focus and sets the direction for the rest of the paragraph. For example, in a paragraph comparing and contrasting two characters in a novel, the topic sentence may introduce the thesis that discusses their similarities and differences.
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