What is included on the back of the passport card?

The correct answer highlights that the back of the passport card includes the Machine Readable Zone (MRZ) and microline printing, which are crucial for automated reading and verification of identity. The MRZ consists of specific lines of data that can be read by machines at border crossings, enhancing the speed and efficiency of processing travelers. Additionally, microline printing is a security feature that helps prevent counterfeiting by including fine lines of text that are difficult to replicate.

The inclusion of these features on the passport card provides a reliable means of identification and adds layers of authentication, contributing to overall border security.