An administrator confirmed that the company's public website keeps presenting a certificate warning asking whether this site should be trusted when accessing it over HTTPS. Which of the following is…

A missing private key would prevent the TLS handshake from completing at all, causing a connection failure rather than a trust warning.

The public key is embedded within the certificate structure itself and cannot be absent from it - its absence would produce a malformed certificate error, not a trust prompt.

An intermediate CA issue would typically produce a specific chain error message rather than a general site-trust prompt, and many browsers attempt to auto-fetch missing intermediates.

Browsers and operating systems maintain a pre-installed list of trusted root Certificate Authorities. If a certificate is signed by a CA not in that store - such as a self-signed certificate or a private internal CA - the browser cannot verify the chain of trust and presents a warning asking the user whether to proceed. This is the most common cause of generic trust prompts on public websites.