1f56bc31_ox_vs_App___SharePoint_Dragons__Farm
[0] Runs cross-domain [Sandbox] No, and there’s no need to since code runs within the SharePoint farm. [Apps] Yes, which provides a very interesting way to distribute server loads. [Farm] 
No, and there’s no need to since code runs within the SharePoint farm.
SharePoint 2013: What to do? Farm solution vs Sandbox vs App | SharePoint Dragons
Farm