Final answer:
The student should search for a quotation that aligns with the main idea of the essay and directly supports the overall purpose.
Step-by-step explanation:
The student is asking for a quotation from the essay that directly supports the overall purpose. To find the quotation, the student should look for a statement in the essay that aligns with the main idea. Typically, this would be a sentence or a few sentences that provide evidence or examples to support the thesis. The student can search for keywords or phrases related to the main idea and then look for the corresponding quotation in the essay. It is important to choose a quotation that clearly and directly supports the overall purpose stated in Part A of the question.