Answer: C
Correct answer: It encrypts the connection so data cannot be read or altered in transit
HTTPS is HTTP carried inside a TLS-encrypted connection. It provides three things: confidentiality, so the traffic cannot be read; integrity, so it cannot be altered undetected; and authentication, so the browser can verify it is talking to the genuine site. The authentication rests on a certificate issued by a certificate authority, binding a public key to a domain name. The browser checks the signature chain and shows a padlock when it succeeds - and a warning when it does not, which is why certificate errors should never be clicked past. A point worth understanding: the padlock proves the connection is secure and that the site is who its certificate says. It does not prove the site is trustworthy, and phishing sites routinely use valid certificates. HTTPS is now the default; browsers mark plain HTTP as insecure, and free certificates from Let’s Encrypt removed the cost barrier.