Acredito que a questão esteja desatualizada, de qualquer forma pra mim ambos B e C estão corretos.
TLS veio a substituir o SSL. O HTTPS funcionar tanto com TLS quanto com SSL, mas se for pra ser o mais atual possível, TLS seria o mais correto.
https://en.wikipedia.org/wiki/HTTPS
The HTTPS uniform resource identifier (URI) scheme has identical syntax to the standard HTTP scheme, aside from its scheme token. However, HTTPS signals the browser to use an added encryption layer of SSL/TLS to protect the traffic. SSL/TLS is especially suited for HTTP since it can provide some protection even if only one side of the communication isauthenticated. This is the case with HTTP transactions over the Internet, where typically only the server is authenticated (by the client examining the server's certificate).