A network administrator wants to ensure that network traffic is highly secure while in transit. Which of the following actions best describes the actions the network administrator should take?

The best action to ensure highly secure network traffic in transit is to use only encrypted protocols like TLS. Encryption protects data confidentiality and integrity as it moves across the network, making it unreadable to unauthorized parties. Permitting only authorized traffic via these secure protocols further restricts access and reduces the attack surface. While important, the other options don't directly address securing data in transit as comprehensively: NAC and updated firewall policies control network access and block unauthorized traffic, but don't inherently encrypt data in transit. Configuring IPS to block specific attacks like directory traversal and updating signatures is crucial for threat prevention, but doesn't ensure all traffic is secure in transit. EDR software monitors for unauthorized applications on endpoints, which is vital for endpoint security, but not the primary method for securing network traffic itself.