Which scenario would most likely reveal credentials due to plaintext transmission?

• A. Using HTTPS
• B. Using FTP
• C. Using TLS
• D. Using SSH

Answer: (B)

The scenario tests the risk of credentials being exposed when they’re sent without encryption. In standard FTP, the login sequence transmits the username and password in clear text over the control channel. Because there’s no encryption protecting that portion of the traffic, someone sniffing the network can read the credentials directly, making it easy to capture.

In contrast, HTTPS runs over TLS, so HTTP requests (including any credentials) are encrypted in transit. TLS itself provides the encryption layer for various protocols, so it protects the data exchanged. SSH also encrypts its entire session, so login credentials aren’t sent in plaintext there either. Therefore, the insecure choice that would most readily reveal credentials due to plaintext transmission is using FTP. If a secure variant like FTPS or SFTP is used, credentials would be protected.