Which security feature was added to the I-551 in 1997?

The correct answer is Photo ID, which was a significant enhancement to the I-551 card, also known as the Green Card, in 1997. The introduction of a photo ID feature was aimed at improving identity verification and reducing fraud. By requiring an individual's photograph on the card, it allowed law enforcement officials and border control agents to more easily confirm that the document belonged to the person presenting it. This addition marked a critical step in ensuring the security and integrity of immigration documents, making it more difficult for individuals to misuse or counterfeity these forms of identification.

The other features mentioned, such as biometric identification, QR codes, and biochips, represent advancements that were developed after 1997 and are not associated with the I-551 card from that year. Biometric identification includes elements like fingerprints or iris scans, which were not included in the 1997 design. Similarly, QR codes and biochips were not implemented until later technological advancements improved immigration documentation. Thus, the photo ID feature stands out as the key update to the I-551 in 1997, aligning with the goals of enhancing authentication and combating document fraud.