Which of the following processes is used by remote users to make a secure connection to internal resources after establishing an Internet connection?

Packet filtering is a firewall technique that permits or denies traffic based on rules; it controls access but does not establish a secure remote connection.

Tunneling wraps private network packets inside a protocol (such as IPsec, L2TP, or SSL/TLS) to create an encrypted point-to-point path across an untrusted public network. This is the foundational process behind VPNs, allowing remote users to securely access internal resources as if they were on the local network. The tunnel both encapsulates and protects data from interception during transit.

Packet sniffing is the passive capture and analysis of network traffic, an eavesdropping or diagnostic technique, not a connection-establishment method.

Spoofing involves forging source addresses or identities to deceive systems; it is an attack vector, not a legitimate secure-access mechanism.