In an argumentative essay, reasons should be supported by strongly expressed opinions. details, statistics, and facts. several thesis statements. a number of counterclaims.

The answer is: details, statistics, and facts.

The purpose of an argumentative essay is as a medium for the writer to change the readers' way of thinking so it become similar to the way of thinking of the writer.

Adding details, statistics, and facts would give an implication that the writer has a high amount of expertise in the topic. This data will also make the argument given by the writers become much more believable.