Which of the following is a benefit of Priority Mail Express?

Priority Mail Express offers a guaranteed delivery service that ensures customers can expect their packages to arrive within a specified timeframe. This benefit is a significant selling point for those needing reliable and urgent shipping options, as it provides peace of mind for both senders and recipients. The service is designed for high urgency, often providing next-day or even same-day delivery, depending on the destination and the time of mailing, which is a substantial advantage for users needing timely delivery.

In contrast, the other options do not align with the benefits offered: same-day delivery is not exclusively provided; delivery can occur on weekends in some locations; and while residential delivery may come with certain conditions, the emphasis on additional fees is not a defining feature of the service. Priority Mail Express's reliability and the guarantee it offers set it apart, making it a appropriate choice for those requiring fast and dependable mail services.