How do I send Control Alt Delete from a Mac to a remote Windows PC [closed]
Depends on how you're controlling the remote PC. On most remote control software, you select "Ctrl-Alt-Del" from the menu to send the command to the remote PC.
The option key on the mac keyboard is also labeled alt and there is usually a delete key, too on larger / external keyboards.
With MS Remote Desktop Connection, fn+Ctrl+Alt+Del works fine.