Which of the following provides packet-level encryption between hosts in a LAN?

PPTP (Point-to-Point Tunneling Protocol) is a VPN protocol used primarily for remote access tunneling by encapsulating PPP frames, and does not provide native packet-level encryption between hosts on a LAN.

IPsec provides packet-level security at Layer 3 of the OSI model using the ESP (Encapsulating Security Payload) protocol in transport mode, which encrypts and authenticates each IP packet between communicating hosts without requiring a tunnel - making it the correct choice for direct host-to-host encryption within a LAN.

PFS (Perfect Forward Secrecy) is a cryptographic key exchange property ensuring that compromise of long-term keys does not expose past session keys - it is a characteristic of key negotiation, not a standalone encryption protocol.

Tunneling protocol is a broad generic category describing protocols that encapsulate traffic for transport, not a specific protocol that provides packet-level encryption between LAN hosts.