Final answer:
Asking an open-ended question is an effective technique to capture attention in a sales letter, as it engages and encourages readers to think about how the offering can benefit them. Rhetorical questions and anecdotes also unify the text and make it memorable, while convincing evidence strengthens the argument.
Step-by-step explanation:
Asking a question is an effective way of gaining attention in a sales letter. By posing an open-ended question, readers are drawn in and engaged, as it encourages them to consider their own needs and how the product or service being offered might meet those needs. This approach builds a connection with potential customers and differentiates the sales letter from generic correspondence.
Using rhetorical questions or captivating anecdotes can emphasize points and unify a text, making the content more memorable. Moreover, supporting claims with convincing evidence, including expert opinions, relevant anecdotes, statistics, and facts, can substantiate the argument presented in a sales letter, further capturing the reader's attention and fostering trust.