What protocol is used for secure data transmission in Apple devices?

The correct answer focuses on TLS (Transport Layer Security), which is the standard protocol used for securing data transmission across networks, including those used by Apple devices. TLS encrypts the data during transmission, ensuring that sensitive information, such as passwords and personal data, cannot be easily intercepted or accessed by unauthorized parties. This layer of security is crucial for maintaining privacy and integrity in communication over the internet.

In contrast to other protocols listed, such as FTP, HTTP, and SMTP, TLS specifically provides encryption and secure communication features that protect data. FTP is used for transferring files but does not offer encryption. HTTP is used for transferring web pages but lacks security unless it is combined with TLS (resulting in HTTPS). SMTP is used for sending emails but also does not provide encryption on its own. Therefore, TLS stands out as the best choice for secure data transmission.