Which of the following would be the most appropriate way to protect data in transit?

SHA-256 is a cryptographic hash function that produces a fixed-size output from input data. While it is useful for ensuring data integrity, it does not provide encryption or secure communication on its own. Therefore, it cannot adequately protect data in transit, as it lacks the necessary features for secure transmission.

SSL 3.0 is an older protocol designed to secure communications, but it has known vulnerabilities that can be exploited by attackers. Its use is now discouraged in favor of more secure protocols like TLS. Thus, while SSL 3.0 was once a standard, it is not suitable for current data protection needs in transit.

AES-256 is a symmetric encryption algorithm that provides strong encryption for data at rest or in transit. However, by itself, it does not establish a secure communication channel. It requires a protocol like TLS to facilitate secure data transmission. Therefore, while AES-256 is strong, it is not the most appropriate choice for protecting data in transit without a transport layer protocol.