the introduction of an argumentative essay must include a claim. a citation. a quotation. a summary.

Brief Explanations:

An argumentative essay aims to persuade the reader. The introduction sets the stage. A claim (the main argument) is essential here as it tells the reader what the essay will argue. Citations (sources) are usually in the body for evidence. Quotations (direct words from sources) are also in the body. A summary is for the conclusion (recapping main points).

Answer:

a claim.