Which Type 3 authenticator can be used on its own rather than in combination with other biometric factors?

The correct answer is palm scans because they can serve as a stand-alone biometric identifier due to their unique characteristics and the ease with which they can be captured. Palm scans analyze the patterns of ridges, lines, and creases on the palm, which are distinctive for every individual, making them a reliable form of biometric authentication.

Palm scans function effectively on their own without requiring the combination of additional biometric factors, offering convenience and effectiveness while still maintaining a high level of security. Other biometric factors like fingerprints, retina scans, and voice recognition may also be used for authentication, but they typically are more effective when used in conjunction with other factors to enhance security and accuracy. For example, fingerprints are often enhanced with additional authentication methods due to potential issues with impression quality or environmental factors. Similarly, retina scans and voice recognition can benefit from additional factors to reduce the risk of false acceptance rates or spoofing. Therefore, palm scans are uniquely suited to serve as a standalone authenticator.