Which postal service is specifically designed for sending packages internationally?

The choice of International Priority Mail is the correct answer because it is a specialized postal service tailored specifically for the international shipping of packages. This service is designed to provide timely and reliable delivery of parcels to destinations outside of the sender's home country.

International Priority Mail typically includes features such as tracking, defined delivery times, and options for various forms of delivery confirmation, making it ideal for individuals and businesses that need to send packages abroad efficiently. It ensures that items are processed and shipped according to international standards, which is crucial for timely delivery across borders.

In contrast, Domestic Priority Mail is limited to shipping within the same country and therefore does not apply to international shipments. Express Mail can also be used for urgent deliveries but may not have the same dedicated international focus as International Priority Mail. Standard International Mail, while it does cater to international shipping, generally offers longer delivery times and lacks the expedited features that come with International Priority Mail. Thus, International Priority Mail is the most suitable choice for sending packages internationally.