Answer:
D. Place them in the demilitarized zone.
Explanation:
Demilitarized zone(DMZ) is a logical or physical sub network that contains and gives exposure to an organization's external-facing services to an not trust worthy network, basically a larger network like Internet. It's purpose is to add an extra layer of security in an organization's LAN(local area network).So we conclude that DMZ is best way so that intruder cannot access the intranet.