You are troubleshooting long delays between FortiMail file submissions to FortiSandbox and verdicts being returned...

The FortiSandbox 5.0 Administrator Lab Guide shows that, when diagnosing FortiMail submission issues, the required FortiMail debugs are sandboxclid and deferd . It explicitly instructs: “Enter the following commands to enable both deferd and sandboxclid debugging” and then shows that the deferd daemon spools the email and later releases the email from the queue folder after FortiSandbox processing.

Because sandboxclid is not one of the answer choices, the best answer among the listed FortiMail debug tools is deferd . It is the FortiMail daemon directly shown in the official lab workflow for troubleshooting submission-and-verdict handling. The other options in the answer list are not the ones the lab uses for FortiMail-to-FortiSandbox submission troubleshooting. So, based on the uploaded guide, diagnose debug application deferd is the correct choice.