When a host processes an inbound IPSec packet, how does it determine which IPSec protocol to use to process the packet?

1) The host determines the IPSec protocol by looking at the selector values of the packet.

2) The host determines the IPSec protocol by looking at the 8-bit protocol field of the IP header.

3) The host determines the IPSec protocol by looking up an appropriate entry in the Security Association Database.

4) The host determines the IPSec protocol by looking up an appropriate entry in the Security Policy Database.

5) None of the above.