You want to customize access to the corporate network so that agentiess users are instructed to obtain a certificatebefore accessing the network.Which two configurations solve this problem? （）

• A、Create a custom sign-in page with specific instructions in the "Instructions" field.
• B、Create a custom sign-in page with specific "Missing Certificate" messages in the "Custom error messages" field.
• C、Create a custom sign-in policy with specific instructions in the "Instructions" field.
• D、Create a custom sign-in notification and assign it to the "Pre-Auth Sign-in Notification" in the sign-in policy.