The least expensive and most trustworthy biometric authentication method is ?FingerprintAttendence MethodsRetina scanningBadges

To determine the least expensive and most trustworthy biometric authentication method among the options provided (Fingerprint, Retina scanning, Attendance Methods, Badges), we will evaluate each option based on cost and reliability.

1. Fingerprint Authentication: Fingerprint scanners are generally affordable and widely used in various applications. They offer good accuracy and have low false acceptance rates. The technology is mature, making it a cost-effective solution.

2. Retina Scanning: Retina scanning is highly accurate and secure, but the equipment is much more expensive compared to fingerprint scanning. It also requires specialized conditions and can be invasive, which may deter users.

3. Attendance Methods: This term could refer to various methods, including biometric ones like fingerprints or facial recognition. However, if it’s more general and includes non-biometric methods (like traditional roll-call), it may not provide the same level of security as biometric options.

4. Badges: Badge systems can be cost-effective, especially in terms of initial setup. However, they can be easily lost, stolen, or replicated, undermining their security.

Conclusion: Based on the analysis, the least expensive and most trustworthy biometric authentication method tends to be Fingerprint Authentication, as it strikes a balance between affordability and effectiveness in securing access control.