What captures the details of suspected short-paid packages and charges the mailer for any postage due?

The correct answer is based on the process that specifically pertains to identifying and managing issues related to short-paid packages. Short-Paid Package Validation is a system or practice designed to detect packages that do not have adequate postage affixed to them. When a package is identified as short-paid, the system captures the necessary details to determine the amount of postage that was not covered, and subsequently assesses the mailer for the difference. This process ensures that the U.S. Postal Service recoups any lost postage revenue due to inadequate payment at the time of mailing.

In contrast, the other options refer to different systems or practices that do not specifically target the issue of short-paid postage. For example, Automated Package Verification generally refers to ensuring package dimensions and weights are accurately assessed for compliance rather than focusing solely on postage due. Delivery Confirmation Tracking relates to tracking packages to confirm their delivery status, and Package Invoice Verification involves reviewing invoices for accuracy but does not specifically address the collection of short-paid postage. Each of these options serves distinct functions that do not overlap with the specific validation of short-paid packages, which is why Short-Paid Package Validation is the most precise answer.