To strengthen an argument, a writer might consider which of the following tactics?

Including testimonials and data is a powerful tactic for strengthening an argument because it provides concrete evidence to support the claims being made. Testimonials lend a personal touch, showing real-world effects or experiences that resonate with the audience. Data, on the other hand, adds a layer of credibility and objectivity to the argument, as it is based on measurable and verifiable information. Both elements can enhance the persuasiveness of the argument by making it more relatable and grounded in facts, which helps to convince the reader of the validity of the writer's position.