What code sample should a developer use to ensure that HTTPS is utilized in a PaymentForm controller?

To ensure that HTTPS is utilized in a PaymentForm controller, the appropriate code sample should specify that the connection must be secure, which is validated by the inclusion of 'https' in the guard conditions.

In this context, the correct way to enforce this security requirement is to use a guard function that checks for specific protocols and conditions before allowing access to the payment handler. This can be done by specifying 'https' among other relevant parameters such as 'post' for the HTTP method and 'loggedIn' to ensure that the user is authenticated.

The choice that includes 'https' alongside 'post' and 'loggedIn' correctly indicates that the request must be made over a secure connection (HTTPS), while also ensuring that it is a POST request and that the user is logged in, thereby adding a layer of security and ensuring that sensitive payment data is handled appropriately.

Other options either lack the HTTPS requirement or do not sufficiently enforce the necessary conditions for processing payment forms securely. Thus, the selected sample is the most effective and appropriate for ensuring the secure handling of payment processing in a B2C Commerce environment.