Blocked by organization policy : Antimalware policy block by file type

Hi

Can someone please shed some light on this. I am trying to identify if a DLP or Anti-malware policy is blocking an email. The real-time detection has this:

Primary Override : Source
Blocked by organization policy : Antimalware policy block by file type
 
Would this be one of the policies in  policies & rules>threat policies> anti-malware ?
 
I was hoping there would be a setting that can pin-point the policy name or rule. Please advise