Which of the following represents a secure website?

A secure website is indicated by the presence of "https://" at the beginning of the URL. The "s" in "https" stands for "secure," which means that the data exchanged between the user's browser and the web server is encrypted. This is especially important when sensitive information, such as personal data or financial details, is being transmitted online.

In the context of the given choices, the presence of "https://" in the choice that includes Google signifies that it employs security protocols, protecting any data transferred. This is critical for user safety and privacy while browsing or conducting transactions.

Other options, while they may lead to reputable websites, start with "http://" which does not provide the same level of security, indicating that communications with those sites could potentially be intercepted or corrupted. Hence, the correct choice is the one that demonstrates the use of a secure protocol through "https://".